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Teacher: Miss Venditti ENVIRONMENT, SCIENCE & TECHNOLOGY -WORKBOOK- Student Name: _________________________
Transcript of ENVIRONMENT, SCIENCE & TECHNOLOGYmistertam.weebly.com/uploads/2/3/1/4/23148826/est... · 2018. 9....
Teacher: Miss Venditti
ENVIRONMENT, SCIENCE & TECHNOLOGY -WORKBOOK-
Student Name: _________________________
2
TABLE OF CONTENTS
REFERENCES 3
Formulas & Quantities (EST) 4
Formulas & Quantities (ST) 5
MATERIAL WORLD 6
Chapter 1 7
Exercises 13
Chapter 2 15
Exercises 20
Chapter 3 25
Exercises 28
Chapter 4 32
Exercises 38
Chapter 5 43
Exercises 49
TECHNOLOGY WORLD 61
Chapter 12 62
Exercises 64
Chapter 13 65
Exercises 69
Chapter 14 71
Exercises 72
EARTH & SPACE 74
Chapter 6 75
Exercises 77
Chapter 7 78
Exercises 81
Chapter 8 82
Exercises 84
LIVING WORLD 85
Chapter 9 86
Exercises 87
Chapter 10 89
Exercises 91
Chapter 11 92
Exercises 96
3
REFERENCES
4
Formulas & Quantities (EST)
FORMULAS
C = m V
C: concentration W = ΔE W: work m: mass ΔE: Variation in energy V: volume
W = FΔd W: work V = RI V: potential difference F: force
R: resistance Δd: distance travelled I: electric current intensity
Fg = mg Fg: gravitational force Req = R1 + R2 + … Req: equivalent resistance m: mass g: gravitational field
intensity 1 = 1 + 1 + … Req R1 R2
Req: equivalent resistance
E = PΔt E: energy consumed Ep = mgh Ep: gravitational potential
energy P: power m: mass Δt: change in time g: gravitational field
intensity P =VI P: power h: height
V: potential difference I: electric current intensity Ek = ½ mv2 Ek: kinetic energy
m: mass Fe = kq1q2 r2
Fe: electric force v: velocity k: Coulomb’s constant q: Charge of particle Q = mcΔT Q: Quantity of heat r: Distance between two
particles m: mass
c: specific heat capacity ΔT: change in temperature
QUANTITIES
NAME SYMBOL VALUE (for water)
Coulomb’s constant k 9 x 109 Nm2/C2
Gravitational field intensity on earth g 9.8 N/kg
Specific heat capacity c 4.19 J/(g°C)
Resistor Colour Code Chart
Colour Black Brown Red Orange Yellow Green Blue Purple Grey White
Digit 0 1 2 3 4 5 6 7 8 9
Multiplier 100 101 102 103 104 105 106 107 108 109
Tolerance: gold ± 5%, silver ± 10%, black ± 20%
5
Formulas & Quantities (ST)
FORMULAS
C = m C : concentration V m : quantity of solute V : quantity of solution V = RI V : potential difference R : resistance I : electric current intensity
P = VI P : electrical power V : potential difference I : electric current intensity E = P∆t E : energy consumed P : electrical power ∆t : time difference
Energy efficiency = __Amount of useful energy__ x 100 Amount of energy consumed
QUANTITIES
NAME SYMBOL VALUE
Density of water
Kilowatt-hour
kWh
1.3 g/mL
or 1.0 kg/L
or 1000 kg/m3
1 kWh = 3 600 000 J
6
MATERIAL WORLD
7
CHAPTER 1
Atomic Theories:
Democritus (400 BC): (p. 6) Thought matter was discontinuous
Philosopher
o He thinks – doesn’t test his ideas (experiment)
Stated:
o All matter is made up of tiny indivisible particles, which he calls atoms
Aristotle (350 BC): (p. 6)
Thought matter was continuous
Philosopher
Stated:
o You cannot detect atoms with your senses (can’t see, touch, etc) o All matter is made up of 4 major components (earth, wind (air), heat
(fire), and water)
Example of classification:
Dalton (1808 AD): (p. 8)
He used Democritus’ model as a starting point and assumed that matter is composed of tiny indivisible particles
called atoms Conducted experiments with masses of elements and compounds
o Ex: water is composed of 8g of O2 (oxygen) to every 1g of H2 (hydrogen)
Stated:
o All atoms of the same kind are identical o Atoms of different elements are different
o During chemical reactions, atoms tend to combine to form compounds
Thomson (1897 AD): (p. 8)
Made his observations from:
o Static electricity (electrostatics) o Cathode ray tubes
Stated:
o An atom consists of a positive sphere
o Negatively charged particles are embedded on the surface of the sphere (atom)
Named the electron (negatively charged particle)
Rutherford (1911 AD): (p.11) Rutherford identified radioactive rays (discovered by H. Becquerel, 1896):
o Alpha () particles – positive charge
o Beta () particles – negative charge
o Gamma () particles – neutral charge
By firing alpha particles at gold leaf, Rutherford observed & concluded:
Observation Conclusion
Most of the alpha particles pass through the
gold foil without being deflected An atom is mostly empty space
Some alpha particles are strongly deflected
or bounce back
An atom contains a very dense and
very small nucleus
The nucleus of an atom is positively
charged
Rutherford concluded that the center is the nucleus of the atom
Also stated that the electrons circle the atom like planets orbiting the sun
Stone Human
Earth 70% 10%
Wind 18% 15%
Heat 10% 5%
Water 2% 70%
8
Bohr-Rutherford (1913 AD): (p. 13)
N. Bohr improved Rutherford’s model by specifying that electrons weren’t
randomly distributed, but on specific orbits (rings) A model of the atom that has a small nucleus with protons found inside,
surrounded by electrons moving in orbits
Simplified Atomic Model (1932 AD): (p. 15) J. Chadwick discovered the neutron
o Particle found inside the nucleus with no electrical charge (neutral)
o Contributes to the total mass of an element To calculate the # of neutrons:
o Neutrons = Average Atomic Mass – Atomic Number
The Periodic Classification of the Elements:
Periodic Table:
The periodic table of elements is a visual representation of the elements in groups according to their physical and
chemical properties
Groups:
o Each column is called a group
o The group number represents the number of valence electrons The number of electrons in the last ring or orbital Ex: Halogens are in group VII – they all have 7 electrons in the last ring
Periods:
o Each row is called a period o The period number represents the number of rings or orbital
Ex: Period 3, each element has 3 rings in their simplified atomic model
Staircase:
o The staircase is a dividing line between metals and nonmetals Metals are found to the left of the staircase
Nonmetals are found to the right of the staircase Metalloids are found along the staircase
Metals, Nonmetals & Metalloids:
Properties of metals:
o They are shiny (metallic luster)
o They are good conductors of heat and electricity o They are malleable (they can be bent without breaking) and ductile (they can be drawn out into wires)
Staircase
Periods
Groups
9
o Several of them react with acids
Properties of Nonmetals:
o They are lusterless (no shine)
o They are poor conductors of heat and electricity o They cannot be made into sheets or drawn into wires
Metalloids share properties of both metals and nonmetals
o The metalloids are:
Boron (B); Carbon (C); Silicon (Si); Gallium (Ga); Germanium (Ge); Arsenic (As); Selenium (Se); Antimony (Sb); Tellurium (Te); Bismuth (Bi); Polonium (Po); and Astatine (At)
The Groups of the Periodic Table:
Alkali Metals (Group I):
o Properties:
Soft, light metals that melt at low temperatures Found combined with other elements (never found as
free elements) Excellent conductors Highly reactive with water and air
o Uses: Alkali metals are mostly used as compounds Sodium chloride (table salt)
Sodium bicarbonate (baking soda) Lithium used to treat depression
Sodium and potassium nitrates (fertilizers)
Alkaline Earth Metals (Group II):
o Properties:
Grey, metallic solids that are excellent conductors Also reactive with air and water, but less violent than
alkali metals Melting points are higher than alkali metals
o Uses:
Magnesium is used in fireworks and flash bulbs
Calcium salts are used to melt ice on the road Barium sulfate is used in fluoroscopy (to see your
stomach)
Halogens (Group VII):
o Properties: Nonmetallic properties These elements are very reactive (in nature they exist
only in combined states – diatomic) They form salts when combined with alkali metals
They form strong acids in combination with Hydrogen They are toxic and corrosive
o Uses:
Iodine is essential to the proper functioning of the thyroid gland – it’s added to table salt (iodized table salt)
Chlorine is used to disinfect drinking water (used in
bleaching agents and some antiseptics) Fluorine (the most reactive) used for frosting glass
Noble Gases or Inert Gases (Group VIII):
o Properties:
Lack of chemical reactivity
Under ordinary conditions, they don’t form compounds with other elements
10
o Uses: Used to manufacture coloured light in illuminated signs (Ex.
Neon lights)
Helium is used to inflate balloons
Argon is used to fill light bulbs and electronic flashbulbs
Hydrogen
o Hydrogen is a one-of-a-kind element that does not belong to a chemical group
Sometimes it behaves like an alkali metal
Sometimes it behaves like a halogen
EST – Predicting Properties from Periodic Trends: 1. Ionization Energy:
a. It is the minimum Energy required to remove one electron from each of a given quantity of atoms.
b. If the ionization energy of an element is large, then it is difficult to remove an electron from an atom of the element.
c. Trend: i. Generally low in metals (especially group IA & IIA)
ii. Highest in non-metals (especially group VIIIA)
Note: An ion is a charged atom – positive ions lose electrons and negative electrons gain electrons.
2. Electronegativity: a. It is a measure of an elements relative attraction for electrons when it is chemically combined with another
atom
b. Trend: i. Very low in group IA, IIA & VIIIA
ii. Very high in the non-metals (especially in group VIA & VIIA)
Note: Metals lose electrons and nonmetals gain electrons (except group VIIIA)
3. Atomic Radius: a. It is a measure of the size of the neutral atom
b. Trend:
i. Generally increases down each group ii. Generally decreases across each period
4. Electrical Conductivity:
a. Trend: i. Generally high in metals
ii. Towards the middle, metals are the best conductors (copper, silver, gold)
5. Thermal Conductivity:
a. Trend: i. Generally high in metals
6. Melting Points\Boiling Points: a. Trend:
i. Metals tend to have higher melting and boiling points than nonmetals (i.e. metals require a higher temperature to melt)
ii. Higher melting points in the middle
EST – Relative Atomic Mass:
1. Isotopes: a. Isotopes are different types of a single element – “cousins”
b. An isotope is named by its mass c. Ex: The isotopes of Hydrogen
11
Diagram Atomic # Isotope Name Common Name Chemical Notation
1p+
0n0 1 Hydrogen-1 Hydrogen (Protium)
1H
1p+ 1n0 1 Hydrogen-2
Hydrogen
(Deuterium)
2H
1p+
2n0 1 Hydrogen-3 Hydrogen (Tritium)
3H
2. Calculating Relative Atomic Mass: a. Relative atomic mass for a given element is an average of the masses of its isotopes based on the
abundance (availability)
b. Formula: (Isotope 1 x abundance 1) + (isotope 2 x abundance 2) + ….
Ex: Element X
Isotope Abundance
X-84 0.5 %
X-86 9.9 %
X-87 7.0 %
X-88 82.6 %
Step 1: Change the abundance from a percentage to a decimal.
Step 2: Calculate the relative atomic mass using the above formula.
84(0.005) + 86(0.099) + 87(0.07) + 88(0.826) = 87.712 amu
Note: the units for relative atomic mass μ or amu (atomic mass unit)
Representing Atoms:
Lewis Notation Rutherford-Bohr Model
Simplified Atomic Model (EST) Ball-and-Stick
8 p+
1 p+ 1 p+
1
1
1
12
EST – Molar Concentration:
1. Avagadro’s Number: a. Because 1 atom is so small it is almost impossible to calculate its mass
b. A set number of atoms (6.023x1023 atoms) was determined to find mass
c. Just like 1 dozen = 12, 1 mole = 6.023x1023 atoms
2. How to Calculate Molar Mass: a. On the periodic table we can find the average atomic molar mass
b. If given a molecular formula, you can determine the mass of 1 mole of that compound.
3. How to Calculate the Number of Moles:
a. To calculate the number of moles use the formula:
n = Mass of Solute n = the number of moles Molar Mass
Ex: How many moles does 250 g of H2SO4 have?
n = 250_
98.03
n = 2.55 moles of H2SO4
4. How to Calculate Molar Concentration: a. Molar concentration is also referred to molarity
b. To calculate concentration use the formula:
Concentration = Solute_ Solute = # of moles
Solution Solution = Volume (L)
Ex: Find the concentration of 3 moles of KOH in 450 ml of solution.
Concentration = 3 mol_ 0.45 L
Concentration = 6.67 mol/L of KOH
5. How to Calculate Molarity Given Solute as a Mass:
a. Ex: Find the molarity of 256 g of KOH in 250 ml of solution b. To calculate the molarity follow the same 3 steps:
Step1: Calculate the molar mass of the solute.
1 mole of KOH K: 1 x 39.1 O: 1 x 16.0
H: 1 x 1.01 56.11 g/mol
Step 2: Calculate the number of moles of solute.
n = 256_
56.11 n = 4.56 moles of KOH
Step 3: Calculate the concentration of the solution.
Conc. = 4.56
0.25
Conc. = 18.25 mol/L of KOH
Ex: H2SO4 H: 2x1.01 = 2.02
S: 1x32.01 = 32.01 O: 4x16 = 64.0
98.03 g/mol
13
Exercises:
1. Who believed that all matter was composed of four basic elements – earth, fire, water & air? a. Aristotle
b. Democritus
c. Dalton d. Thomson
2. Which of the statements below are NOT part of the four characteristics of Dalton's atomic model:
1. An atom has electrons and protons
2. Atoms of different elements are identical. 3. Atoms of the same elements are the same.
4. Atoms come in all sizes, shapes and textures. 5. Atoms of different elements are different.
6. Atoms can be rearranged to produce new substances
a. 1, 2, 4, 5, 6 b. 1, 2, 5, 6
c. 1, 2, 4 d. 2, 4, 5, 6
3. Democritus and Aristotle developed their own models about the structure of matter. Below is some statements made by these scientists.
1) Matter consists of tiny particles that cannot be divided. 2) Matter is made up of four elements (earth, water, fire and air).
3) Matter could be divided into smaller particles.
4) Matter was discontinuous.
Which of the above statements were made by Aristotle?
a. 1 and 2
b. 1 and 3 c. 2 and 4
d. 3 and 4
4. The chart below describes four elements that could be found in the periodic table. Carefully read each question and decide which elements (A, B, C, or D) belong to the same group or family?
Element A This element from Period 3 has 8 valence electrons.
Element B This element is from Period 2 and has 6 less valence electrons than inert gases.
Element C This metal from Period 4 has two valence electrons and is found in milk.
Element D This element has properties from both the metals and the nonmetals and is found in
Period 4.
a. C and D
b. A and B
c. A and D d. B and C
5. In the past, there were a variety of atomic models that developed over the years that explained the structure of
matter. Place the following in order of most recent to most ancient according to our studies.
1. Thomson’s “Plum-Pudding” model 2. Dalton’s atomic model
3. Rutherford’s atomic model 4. Bohr-Rutherford’s atomic model
5. Democritus and Aristotle
a. 5, 4, 3, 2 and 1 b. 1, 4, 3, 2 and 5
c. 4, 2, 3, 1 and 5 d. 4, 3, 1, 2 and 5
14
6. State the element that corresponds to the following statements.
a. Has 4 energy or electron shells & 2 valence electrons. b. Has 3 valence electrons & 2 electron shells.
c. An alkaline earth metal with 2 electron shells.
d. Non-reactive nonmetal with 2 electron shells. e. Very reactive, tends to gain electrons & has 3 electron shells.
f. Has 4 valence electrons & 2 electron shells. g. Loses 1 electron during reactions & has 2 electron shells.
h. Is a metalloid with 3 electron shells.
7. Draw the Lewis diagram and Rutherford-Bohr atomic model for each of the following elements.
a. Sodium b. Phosphorus
c. Potassium d. Sulfur
e. Silicon
Periodic Trends:
1. What can be said of the atomic radius within a period? a. It increases in the elements from left to right.
b. It decreases and then increases in the elements from left to right.
c. It is a constant in the elements. d. It decreases in the elements from left to right.
2. What can be said of the melting point within a
cycle of the periodic table? a. It is higher from the alkali metals than
for the inert gases b. It increases from left to right
c. It is a constant for all the elements
d. It is lower for the alkali metals than for the inert gases.
3. The properties of the elements in the periodic
table vary from one element to another. Four of these variations are:
Which of these variations occur(s) as one goes from one element with a lower atomic number to one with
a higher atomic number within the same period?
a. 1 b. 1 and 3
c. 2 and 4 d. 1, 2 and 3
4. The following graph shows the ionization energies of certain elements as a function of their atomic numbers:
According to this graph, which of the following statements is true?
a. Within a period, the ionization energy usually
increases as the atomic number increases. b. Within a period, the ionization energy usually
decreases as the atomic number increases.
c. In general, the ionization energy of the elements in Period 3 is greater than the ionization energy
of the elements in Period 2. d. The ionization energy of the elements in Period 4
varies regularly when the atomic number increases regularly.
1. Increase in electrical conductivity
2. Increase in chemical activity
3. Increase in atomic radius 4. Increase in metallic lustre
15
Isotope Mass
Number
Relative
abundance
1 63 amu 69.1 %
2 65 amu 30.9 %
Isotopes:
1. Which of the 5 hypothetical atoms are isotopes of the same element?
40V20 40W22 42X20
80Y42 40V22
a. V and W
b. W and Z
c. X and Z d. V and X
2. Calculate the atomic mass of element X from the following table.
a. 63.54 amu
b. 63.62 amu c. 64.00 amu
d. 64.38 amu
3. In nature the abundance of isotopes of an element is very unequal. For example, the following table represents the
isotopic composition of oxygen.
Mass Number % abundance
16 99.772
17 0.038
18 0.200
The atomic mass of oxygen is practically the same as one of its isotopes. Which is it and why?
4. The following table lists the characteristics of element A.
Isotope Atomic
Number
Mass
Number
Relative
abundance
1 22 45 amu 10 %
2 22 46 amu 75 %
3 22 47 amy 15 %
Calculate the atomic mass of element A a. 22.00 amu
b. 46.00 amu
c. 46.05 amu d. 47.90 amu
5. The atomic mass varies irregularly from one element to the next in the periodic table. Whuch three statements
explain why this is so?
1. The number of neutrons may vary irregularly from one element to the next. 2. The number of isotopes may vary from one element to the next.
3. The relative abundance of isotopes may vary from one element to the next. 4. Some elements have radioactive isotopes, while others do not have any at all.
a. 1, 2 and 3
b. 1, 2 and 4 c. 1, 3 and 4
d. 2, 3 and 4
CHAPTER 2
Molecules & Solutions:
Molecules: (p.40) A molecule is a group of two or more chemically bonded atoms
When a metal and nonmetal bond it is called an ionic bond
o The atoms lose or gain electrons
16
When two or more nonmetals bond it is called a covalent bond
o The atoms share outer electrons
Why do atoms bond to form molecules?
Atoms in their pure/natural state are not stable – they want to react
Noble gasses do not form bonds with other elements because they are stable and non-reactive.
o They are in group VIIIA – have a complete outer ring (8 valence electrons)
Therefore, all elements try to attain the same electron configuration of the noble gasses – the Octet Rule
Octet Rule:
To attain the same electron configuration of Noble gasses, some elements will lose electrons or gain electrons
o Loss and gain is dependent upon how “easy” or “hard” it would be to satisfy the octet rule The tendency to gain or lose electrons:
Gro
up
nu
mb
er
IA IIA IIIA IVA VA VIA VIIA VIIIA
Le
wis
dia
gra
m
Li Be B C N O F Ne
# o
f
va
len
ce
ele
ctr
on
s
1 2 3 4 5 6 7 8
(except
He)
Te
nd
en
cy
Lose 1e- Lose 2e- Lose 3e- Lose or
Gain 4e- Gain 3e- Gain 2e- Gain 1e-
None
(stable)
Ion
Li+ Be+2 B+3 C±4 N-3 O-2 F- Ne
Ions:
Generally atoms are electrically neutral (# of protons = # of electrons)
An ion is an atom that has become electrically charged by losing or gaining one or more electrons
Negative ions:
o An atom that gains one or more electrons
o The simplified atomic model will have more electrons than protons (p.42) o The atom has a negative net charge
Positive ions:
o An atom that lost one or more electrons
o The simplified atomic model will have more protons than electrons (p.42)
o The atom has a positive net charge
EST – Polyatomic Ions: (p.44) A polyatomic ion is a group of two or more chemically bonded atoms that has become electrically charged by losing or
gaining one or more electrons Common polyatomic ions:
17
Chemical
Formula Name
Chemical
Formula Name
Chemical
Formula Name
Chemical
Formula Name
CH3COO- Acetate CO3-2 Carbonate OH- Hydroxide PO4
-3 Phosphate
NH4+ Ammonium ClO3
- Chlorate NO3- Nitrate SO4
-2 Sulphate
HCO3- Bicarbonate CrO4
-2 Chromate NO2- Nitrite SO3
-2 Sulphite
EST – Nature of Chemical Bonds: (p.45)
Ionic Bond:
To achieve the octet rule, these atoms gain/lose electrons
metals (positive ions) + nonmetals (negative ions)
o Follows the laws of attraction – opposite charges attract
How to make a formula:
o Use the crossover rule and apply the LCM (lowest common multiple) if applicable
Examples:
Potassium (K) and Phosphorus (P) K+ + P3- = K3P *the charge of the K & P crossed over to form the formula
Magnesium (Mg) and Oxygen (O) Mg2+ + O2- = Mg2O2 = MgO
*the charge of the Mg & O crossed over to form the formula, then
reduced (LCM) to get the formula
Nomenclature (name system):
o Name the metal and add ide to the last element Example:
K3P = Potassium Phosphide
MgO = Magnesium Oxide
Covalent Bond:
To achieve the octet rule, these bonds share outer electrons
Nonmetals + nonmetals How to make a formula:
o Use the crossover rule and apply the LCM if applicable
Nomenclature:
o Use numerical prefixes and add ide to the last element
# 1 2 3 4 5 6 7 8 9 10
Prefix Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca
Example:
CCl4 = Carbon Tetrachloride As2S3 = Diarsenic Trisulfide
Diatomic elements:
o Special case of covalent bonding
o These elements achieve the octet rule by sometimes bonding with themselves
o Diatomic elements are:
I Have No Bright Or Clever Friends
I2 H2 N2 Br2 O2 Cl2 F2 o Nomenclature:
Diatomics are named by their element (ex: H2 is Hydrogen gas)
18
Solutions: (p.50)
A solution is a homogeneous mixture whose component substance cannot be distinguished, even with the aid of a magnifying instrument
Solution = Solute + Solvent
Aqueous solution is a solution in which the solvent is water
Concentration: Ratio of the quantity of solute to the quantity of solution
How to calculate concentration:
Concentrations can also be measured as a percentage or parts per million
o Percentages: Expressed in quantity of mass in 100 parts of solution
Percent volume/volume (%V/V)
o Alcohol is measured in %V/V
o Ex. 11% wine means 11 ml of alcohol (liquid solute) in 100 ml of wine (liquid solution)
Percent mass/volume (%m/V)
o Glucose solutions used in hospitals is measured in %m/V o Ex. 5% glucose solution means 5 g of sugar (solid solute) in 100 ml of aqueous
solution (liquid solution)
Percent mass/mass (%m/m)
o This form is rarely seen in everyday life o Parts per million (ppm):
Certain solutions have very weak concentrations; percentages are of little use Levels of pollution are measured in ppm
Ex. 30 ppm CO level means there is 30 parts CO (solute) in 1 million parts of air (solution)
Dilution: Often solutions have too high of a concentration se we need to add more solvent (usually water) to dilute (weaken)
the original concentration.
How to calculate dilution:
C1 = initial concentration
C1V1 = C2V2 V1 = initial volume of solution C2 = final/diluted concentration
V2 = final/diluted volume of solution Ex 1: (easy)
400 ml of a diluted solution is prepared using 50 ml of an acid solution with a concentration of 16 g/L. What is the
concentration of the diluted solution?
C1 = 16 g/L V1 = 50 ml (0.05 L) C1V1 = C2V2
C2 = ? (16)(0.05) = C2(0.4) V2 = 400 ml (0.4 L) 2 g/L = C2
Ex 2: (hard)
How much water must be added to 185 ml of a 3 g/L solution to dilute it to a 0.2 g/L solution?
C1 = 3 g/L Step 1: C1V1 = C2V2
V1 = 185 ml (0.185 L) (3)(0.185) = (0.2)V2 C2 = 0.2 g/L 2.775 L = V2
V2 = ? Step 2: to find volume of water added (V2-V1) 2.775 – 0.185 = 2.59 L of water added
Electrical Conductivity: (p.55) Electrical conductivity of a solution is a measure of its ability to allow an electric current to flow through it (i.e. an electrolyte)
An electrolyte is a substance that, when dissolved in water, allows an electric current to flow through it.
Concentration (g/ml) = mass of solute (g)_ Volume of solution (L)
19
Types of electrolytes are acids, bases, and salts in an aqueous solution
o Acids:
Generally have an “H” in the front of the formula (ex: HCl) Turns blue litmus paper red
Does not react with phenolphthalein
Tastes sour Reacts with metal to produce hydrogen gas (H2)
Reacts with marble chips (calcium carbonate – CaCO3) to produce carbon dioxide gas (CO2) Can be used to neutralize bases
Examples:
Vinegar, soft drinks, fruit juices, rain water, lemon, gastric juices
o Bases: Generally have “OH” at the end of the formula (ex: NaOH)
Turns red litmus paper blue
Reacts with phenolphthalein (colourless pinkish/purple)
Tastes bitter Slippery and slimy to the touch
Can be used to neutralize acids Examples:
Blood, soaps & detergents, antacids, cleaning products, liquid drain cleaner, baking soda, ammonia
o Salts: Usually ionic bonds
Does not have a “H” in front or “OH” at the end of the formula No effect on litmus paper or phenolphthalein
Tastes salty
Examples: Table salt, bath salts, fertilizers
A non-electrolyte is a substance that doesn’t conduct electricity.
o Conditions for non-electrolytes are:
Not an acid, base or salt Most covalent bonds (except acids)
Organic hydrocarbons (ex: C6H12O6 – glucose)
False bases (ex: CH3OH)
Electrolytic dissociation is the separation of dissolved compound into two ions of opposite charges.
Electrolytic dissociation is a physical change (the nature of the solute
doesn’t change because it was dissolved in water)
The ions formed during electrolytic dissociation is what allows for the
conduction of electricity
pH & Indicators: The level of acidity or alkalinity is determined by its pH
Acids range from 0-7 (strong to weak)
Bases range from 7-14 (weak to strong)
Neutral is exactly 7
Acids Neutral Bases
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Strong Weak Weak Strong
The strength of the pH increases by a factor of ten
20
o Ex. an acid with pH = 3 is 10 times stronger than and acid with pH = 4
o Ex. A base with pH = 8 is 1000 times weaker than a base with pH = 11
Indicators:
An indicator is a substance capable of changing the colour of acids and bases
Common indicators
o Litmus paper (Acids: bluered & Bases: redblue)
o Phenolphthalein (turns pink in the presence of a base)
Other examples are methyl orange, methyl red, bromothymol blue, universal indicator (the most accurate of them
all) pH indicators have their own turning point (the pH at which the colour changes)
o This point is a gradual change (a small range)
To get a more accurate reading/value for the pH of a solution, 2 or more indicators are mixed
Example:
pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Methyl Red Red Orange Yellow
Phenolphthalein Colourless Pink Red
Both Red Orange Yellow
Pink-
Yellow Orange
*The turning point for methyl red is 4.5-6; turning point for phenolphthalein is 7.5-9.5; turning point for both has more colours to be more precise
EST – pH: (p.61) The pH is an indicator of the concentration of H+ ions of a solution
pH – the power of the H+ ions
o Acids contain more H+ ions than OH-
ions
o Bases contain more OH- ions than H+
ions
o Neutral solutions contain equal number of H+ ions and OH-
ions
H+ x OH-
= 1x10-14
pH is expressed as the positive value of an exponent in an H+ ion concentration
pH + pOH = 14
o Ex. of an acid: In a 0.01 (1x10-2) mol/L concentration of HCl, the pH = 2
o Ex. of a base: In a 0.1 (1x10-1) mol/L concentration of NaOH, the pH = 13
In the case of bases, the concentration is that of the OH- ions
Exercises:
Concentrations: 1. Find the concentration, g/L & ppm, for the following situations.
a. 5 mg of HCl dissolved in 2 L of solution
b. 0.25 g of HCl dissolved in 300 ml of solution c. 500 mg of HCl dissolved in 4 L of solution
d. 2.5 g of HCl dissolved in 600 ml of solution e. 300 mg of HCl dissolved in 250 ml of solution
f. 4500 mg of HCl dissolved in 125 ml of solution g. 0.3 g of HCl dissolved in 12 L of solution
h. 0.025 g of HCl dissolved in 3.5 L of solution
i. 4.5 g of HCl dissolved in 700 ml of solution j. 0.08 g of HCl dissolved in 100 ml of solution
2. Calculate the mass of solute needed for the following solutions.
a. 750 ml of a 5.5 g/L concentration
21
b. 4 L of a 0.56 g/L concentration
c. 15 ml of a 75 g/L concentration d. 1.6 L of a 4.8 g/L concentration
Dilution (Review): 1. A lab technician has a flask of 3 g/L of HCl already prepared. She needs to prepare 450 ml of a 1.2 g/L HCl solution.
What volume of concentrate should she use?
2. To dilute 4 L of a solution of concentration 32 g/L to a concentration of 14 g/L, how much water must be added?
3. A can of concentrated fruit juice contains 150 g of solute in 450 ml container. What will be the concentration if the
juice produced by adding three 150 ml cans of water to the concentrated fruit juice?
4. A beaker contains 350 ml of 42 g/L solution. A student added 500 ml of water to this solution. What is the concentration of the diluted solution?
5. A 4 L container of bleach contains an aqueous solution of sodium hypochlorite (NaClO) whose concentration is 60 g/L. Using this solution, you are to prepare 300 ml of another aqueous solution of NaClO whose concentration is 20
g/L. Specify all steps of your procedure and include any calculations.
6. You have 300 ml of an 8% sugar solution. You wish to prepare 120 ml of a diluted 3% sugar solution. Specify all
the steps of your procedure and include any calculations.
7. To dilute 4 L of a solution of concentration 16% to a concentration of 3.5%, how much water must be added?
8. A student prepared a solution by adding 15 g of salt to 250 ml solution. Upon rereading the instructions, he noticed he should have used 8 g of salt. How much water must he add to reach the desired concentrations?
pH & Electrolytes: 1. Based on the following results, what is the identity of each solution?
a. Turned litmus paper red b. pH of 7
c. Slippery to the touch
d. Turns phenolphthalein pink
2. You have a liquid with a pH of 12.6. What can be concluded about the liquid? a. It is neutral
b. It is a weak base
c. It is a strong base d. It is an acid
3. The table below shows the different colours cabbage juice takes when used as an indicator.
pH 3 5 7 9 11 13
Colour Pink Red-Purple Purple Blue Green Yellow
a. What colour(s) would show the presence of a strong base?
b. What colour(s) would show the presence of a weak acid? c. What colour(s) would show the presence of a weak base?
d. What colour(s) would show the presence of a distilled water? e. What colour(s) would show the presence of a strong acid?
4. State whether the following is an acid, base or neutral a. Lemon juice
b. H2SO4 c. Shampoo
d. Ammonia
e. Distilled water
f. NaCl g. Blood
h. Fertilizer
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5. Which of the substance(s) would have a pH less than 7? Which substance(s) would have a pH greater than 7?
Which would have a pH equal to 7? a. H2SO4
b. CaCl4
c. NH4OH d. LiBr
e. CH3COOH
f. Mg(OH)4
g. HCl h. MgO
6. Four tests are carried out on a liquid to determine whether it is a base. The results are shown below:
1. Phenolphthalein turns pink
2. Cobalt chloride paper turns pinkish-beige 3. The liquid conducted electricity
4. litmus paper turned blue
a. 1, 2 &4 b. 1 & 4
c. 1, 3 & 4 d. All tests
7. The following table shows a universal indicator and the different colours it turns in the presence of solutions whose pH values vary from 0 to 14.
pH 1 3 5 7 9 11 13
Colour Green Blue Purple Colourless Pink Orange Yellow
a. What colour(s) would show the presence of a base?
b. What colour(s) would show the presence of a strong acid? c. What colour(s) would show the presence of a strong base?
d. What can be concluded about the solution if it turns colourless?
e. What can be concluded about the solution if it turns pink?
8. You are given 3 different indicators. Their colour changes are shown below.
pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Indicator 1 Yellow Orange Red
Indicator 2 Yellow Brown Violet
Indicator 3 Colourless Pink
a. Draw a diagram showing the pH ranges of the mixture between 1 & 3.
pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14
1 & 3
b. Draw a diagram showing the pH ranges of the mixture between 1 & 2.
pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14
1 & 2
c. Draw a diagram showing the pH ranges of the mixture between 2 & 3.
pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14
2 & 3
d. Draw a diagram showing the pH ranges of the mixture between all three indicators.
pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14
1, 2 & 3
9. The following table shows the colours of four different indicators.
pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Indicator 1 Yellow Green Blue
Indicator 2 Red Orange Yellow Blue
Indicator 3 Colourless Pink Red
Indicator 4 Red Orange Yellow
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You are given a solution, but you don’t know the pH. You pour some of the unknown solution into four different
beakers. In your first beaker, you add drops of the first indicator and it turns green. To your third beaker, you add
drops of the third indicator and it remains colourless. What colour will indicator 2 and 4 be, and what is the pH range of the solution?
10. What condition must be met in order for a material to be electrolytic?
11. State whether the following compounds are: acids, bases, salts or other; ionic or covalent bond and electrolyte or non-electrolyte.
Formula Acid/Base/Salt/Other Ionic/Covalent Electrolyte/Non-Electrolyte
A NaCl
B ZnSO4
C HNO3
D NaOH
E H2O
F CS2
G NaI
H CH3OH
I H3PO4
J CO2
K LiCl
L LiOH
M Ca(OH)2
N NaClO
O MgSO4
P H2
Q PCl3
R K2S
S KNO3
T H2SO4
12. In general, which type of compound (ionic or covalent) dissolves better in water? Explain why.
13. Complete the table below on the properties of acids, bases and salts, indicating the nature of the material.
Acids Bases Salts
Reaction to Litmus
Electrical Conductivity
Touch
Taste
Reaction to Magnesium
Neutralization of…
14. Besides litmus paper, name another indicator. Is it an acid or base indicator?
15. How do you determine if a solution is acid, base or a salt if you don’t have litmus paper?
EST – Naming Compounds: 1. Use the crossover rule to write the formula for the following compounds.
a. Magnesium Oxide __________
b. Sodium Nitride __________
c. Potassium Sulfide __________
d. Aluminum Iodide __________
e. Strontium Fluoride __________
f. Barium Chloride __________
g. Calcium Phosphide __________
h. Sulfur Dichloride __________
i. Dinitrogen Trioxide __________
j. Dichlorine Monoxide __________
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k. Boron Trifluoride __________
l. Aluminum Chloride __________
m. Carbon Tetrachloride __________
n. Calcium Nitride __________
o. Dinitrogen Pentoxide __________
p. Carbon Monoxide __________
q. Sulfur Dioxide __________
r. Barium Hydride __________
s. Barium Oxide __________
t. Sodium Hydride __________
u. Disilicon Hexafluoride __________
v. Bromine Pentafluoride __________
w. Calcium Phosphate __________
x. Potassium Nitrate __________
y. Ammonium Hydroxide __________
z. Ammonium Oxide __________
2. Using the rules for nomenclature, name the following compounds.
Formula Name Formula Name
A NF2 N Cl2O
B H2O O SCl2
C NH3 P CCl4
D NaCl Q KCl
E SiCl4 R PBr3
F MgCl2 S MgH2
G MgO T CaCl2
H CaO U Ca3N2
I BaI2 V BaCl2
J BeH2 W BaF2
K BaO X Na2O
L K2O Y Na3N
M Li2P Z AlF3
3. Complete the chart below.
Solution pH H+ ions OH-
ions
A 10
B 1x10-4
C 1x10-3
D 1x10-1
E 1x10-8
F 7
4. Classify the above solutions from most acidic to least acidic. _____________________________
5. Classify the above solutions from most alkaline to least alkaline. _______________________
6. Joe added 4.5 L of distilled water to a beaker that contained 500 ml of HCl with a concentration of 0.01 mol/L. What
is the new pH of the solution?
7. A bottle with unknown solution contained a liquid with an OH- concentration of 1x10-11. What is the pH of this
solution?
8. Jane uses a solution for her hair that has a pH of 12. What is the hydroxide solution?
9. Bob was asked to mix 2.45 g of H2SO4 in 0.249 L of solution. What is the pH of this solution?
10. Sam was asked to mix 3.8 mg of NH4OH in 100 ml of water. What is the pH of her solution?
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CHAPTER 3
Energy: (p.70) Energy is the ability to do work or effect change.
Energy comes in many forms and a variety of sources:
Form of Energy Description
Elastic Energy stored in an object due to its compression or extension
Electrical Energy resulting from the ordered movement of electrons from one atom to another
Thermal Energy resulting from the random motion of all particles
Radiation Energy contained in and transported by electromagnetic waves
Chemical Energy stored in molecular bonds
Wind Energy resulting from the movement of air
Sound Energy contained in and transported by sound waves
Hydraulic Energy resulting from the flow of water
Nuclear Energy stored in atomic nuclei
Energy is measured in Joules (J) or Newtonmeters (Nm) - (1 J = 1 Nm)
Law of Conservation of Energy: (p.71)
Energy can neither be created nor destroyed; it can only be transferred or
transformed. The total amount of energy in an isolated system always remains constant
Example:
Photosynthesis of plants Solar energy Chemical energy
Energy Efficiency: (p.72)
The energy efficiency of machines or systems corresponds to the percentage of
energy consumed that is effectively transformed:
Formula:
Energy efficiency = Amount of useful energy__ x 100
Amount of energy consumed
Thermal Energy: (p.73) Thermal energy is the energy contained in a substance, determined by the number of particles in the substance and
their temperature (C)
Heat is the transfer of thermal energy between two environments with different temperatures.
o Heat always passes from the warmer to the cooler environment. Formula:
Q = Et Q is the heat (J)
Et is the variation in thermal energy (J)
Heat vs Temperature
Heat is the transfer of energy (a change in temperature) Temperature is a measure of the degree of agitation of the particles of a substance (a single value - temperature)
How to calculate Thermal Energy: (p.75)
Q=mcT Q Thermal energy (J)
m Mass (g)
c Specific heat capacity (J/gC)
T Difference in temperature (C)
The specific heat capacity corresponds to the amount of thermal energy required to raise the temperature of one
gram of a substance by one degree Celsius.
o Each substance has a specific heat capacity
Often thermal energy questions involve water.
o The specific heat capacity – 4.19 J/gC
o 1 ml of water = 1 g of water
26
Example:
Calculate how much thermal energy is needed for a beaker containing 100 g of water to be heated from 20C to
44C.
Q = ? Q = mcT
m = 100 g Q = (100)(4.19)(24)
c = 4.19 J/gC Q = 10 056 J
T = 24C (44C – 20C)
EST – Kinetic Energy: (p.76)
EK = ½ mv2 EK Kinetic energy (J) m Mass (kg)
v Velocity (m/s)
Kinetic energy is the energy an object poses due to motion Sometimes velocity (speed) is given in km/h – it must first be converted to m/s before calculating kinetic energy
o To convert km/h to m/s: 1 km = 1000 m ex: 90 km x 1000 = 25 m/s
h 3600 s h 3600
Example: Calculate the kinetic energy of a car, with mass 2500 kg, travelling 30 m/s.
EK = ? EK = ½ mv2
m = 2500 kg EK = ½ (2500)(30)2 v = 30 m/s EK = 1 125 000 J
EST – Potential Energy: (p.77)
EP = mgh EP Potential energy (J) m Mass (kg)
g Gravity (9.8 N/kg or 9.8 m/s2) h Height (m)
Gravitational potential energy is the energy reserve of an object based on its mass and its height above a reference
surface Example:
Calculate the potential energy acquired by a 2 kg rock raised to a height of 3 m.
EP = ? EP = mgh m = 2 kg EP = (2)(9.8)(3)
g = 9.8 N/kg EP = 58.8 J
h = 3 m
EST – Mechanical Energy: (p.78)
EM = EK + EP EM Mechanical energy (J)
EK Kinetic energy (J) EP Potential energy (J)
The law of conservation of energy states that,
in a system without friction, mechanical energy always remains constant
When objects are in free fall, or you’re on a roller coaster is moving, the amount of kinetic
and potential energy vary depending on position
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EST – Motion: (p.79)
The main variables in motion are speed (velocity), travel, time and acceleration Speed is distance travelled per unit of time
v = d v average speed (m/s)
t d distance travelled (m)
t travelling time (s)
Velocity is speed with a given direction (ex. 100 km/h north) Acceleration is change in velocity over time
a = v a acceleration (m/s2)
t v change in velocity (m/s)
t travelling time (s)
Acceleration is the main effect of applying a force
EST – Forces: (p.80)
A force is an action that can change the motion of an object, or deform the object, by pushing or pulling on it A force is always exerted by one body on another and represented by:
o Horizontal or vertical arrow o Direction is represented by the arrowhead
o The length of the arrow represents the magnitude of the force
Force is measured in Newtons (N)
EST – Types of Forces: (p.81) The most common type of force is gravitational force
o Force of attraction between all objects due to their masses and the distances between them
The intensity of the Earth’s gravitational field at the surface is 9.8 N/kg (or 9.8 m/s2). The field becomes weaker as the distance from the centre of the planet increases.
Gravitational force explains not only falling objects but also phenomenas such as the Earth’s tides and
trajectories of celestial bodies Relationship between mass and weight
o Mass is a measure of the quantity of matter in an object o Weight is a measure of the gravitational force acting on an object
W = Fg = mg W Weight (N)
Fg Gravitational force (N) m Mass (kg)
g Gravitational field intensity (N/kg or m/s2) Example:
Calculate the weight of a 4 kg rock on Earth.
Fg = ? Fg = mg
m = 4 kg Fg = (4)(9.8) g = 9.8 N/kg Fg = 39.2 N
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EST – Effective Force: (p. 88)
The effective force is the force component that alters the motion of an object. It is the component that is parallel to the movement of the object.
(Effective Force) To calculate the effective force use trigonometric formulas for a right angle triangle
Example:
A cart weighing 10 N is placed on an incline at
an angle of 30. Calculate the magnitude of the
gravitational force component, which causes the cart to roll down the plane.
Force of Effective force = Fsin
gravity = (10)sin30
= 5 N
EST – Work: (p.90)
Work is done when a force applied to an object causes it to move – or causes part of it to move – in the same
direction as the force or one of the force components o The force used to calculate work is the effective force
The units for work is Joules (J) – work is a type of energy
W = Fd W Work (J) F Force component parallel to the direction of travel (N)
d distance traveled by the object (m)
Example: Jill pulls with a force of 13 N on a rope attached to a box at
an angle of 23. How much work is needed to pull the box
a distance of 20 m?
Effective force = Fcos
= (13)cos23
= 12 N
Work = Fd
= (12)(20)
= 240 J Exercises:
Thermal Energy:
1. A calorimeter contains 400 ml of water at a temperature of 23C is heated to a temperature of 68C. How much
heat energy was absorbed?
2. A beaker contains one litre of hot water at 78C. After some time, the water cools to 12C. How much heat energy
was lost?
30
29
3. A beaker contains 800 ml of water at 20C. It is heated and the water absorbs 50.4 kJ of heat energy. Determine
the final temperature of the water.
4. A beaker containing water at 24C is placed in a fridge. After some time, the temperature of the water is 5C. If the
water lost 59.7 kJ of heat energy, what was the mass of the water?
5. Wendy pours 0.75 L of tap water into a beaker and heats it to a temperature of 65C. The water absorbs 175 980 J
of heat energy. Determine the temperature of the tap water.
6. Which of the following procedures requires the most energy?
a. Raising the temperature of 10 g of water from 10C to 22C
b. Raising the temperature of 10 g of water from 43C to 55C
c. Raising the temperature of 20 g of water from 72C to 78C
d. Raising the temperature of 20 g of water from 30C to 42C
7. A calorimeter contained 250 g of water at 24C. An electric current was passed through a heater placed in the
water. The heater transferred 14 700 J of energy to the water. What is the final temperature of the water?
8. A water tank contains 200 kg of water. The water is heated by a heating element. How much energy is required to
raise the temperature of the water from 15C to 60C?
9. When a 3500 g block of lead was heated, its temperature increased from 20C to 200C. The specific heat capacity
of lead is 0.13 J/gC. How much heat energy was absorbed by the block of lead?
10. You pour some water that has a temperature of 22C into a calorimeter. You plug in the calorimeter and let the
water heat for 10 minutes. You then note that the temperature of the water has risen to 42C. The quantity of
energy consumed by the calorimeter is 87 000 J. What is the mass of the water in the calorimeter?
11. In the summertime, you find that tap water at 18C is too warm to drink. You put 500 ml of this water in the
refrigerator. After a period of time, the temperature of the water is 4C. While it was cooling, the water lost a
certain quantity of heat energy. What quantity of heat energy was lost?
12. A very thin metallic wire was heated and increased 45C. If the mass of the wire is 28.5 g and yielded 575 J of
energy, what is the specific heat capacity? According to your results, what type of metal could the wire be (p.75 in
text)?
13. 500 g of water is heated from 10C to 35. How much energy was used to heat the water?
14. Daniel decides to make himself a cup of tea. She pours 250 ml of 5C water into her kettle and waits until the water
boils at 100C. How much energy was used to boil the water?
15. On a hot humid summer day, you pour yourself a large glass (750 ml) of cold water at 5C. After 30 minutes
outside, your glass heats up to 20C. How much energy was absorbed by the glass of water?
16. During a lab exam you carry out an experiment and record your results in the table below.
Mass of water 400 g
Initial temperature of the water 40C
Final temperature of the water 81C
Duration of the experiment 25 minutes
How much energy was absorbed by the water?
17. 698 J of energy are used to heat a 25 g iron pan from 23C to 85C. What is the heat capacity of the iron pan?
18. 32 682 J of energy are used to warm water from 26C to 78C. What is the mass of the water?
19. When 425 g of water is heated in a microwave oven, the temperature of the water rose 22C to 47C. How much
heat energy was absorbed by the water?
30
20. A 27C piece of copper absorbs 0.2769 kJ of heat energy to warm up to 98C. If the heat capacity of copper is 0.39
J/gC, what was the mass of the piece of copper?
21. 750 ml of water is heated to 80C. If the heat energy provided was 188 550 J, what was the temperature of the
water before it was heated?
22. 83 800 J of heat are absorbed by 100 g of water. If the water’s initial temperature was 50C, what was the
temperature of the water after it was heated?
23. In an engine cooled with antifreeze, the temperature of 5 kg of antifreeze in its radiator increases from 20C to
100C. What is the specific heat capacity of the antifreeze if it released 880 000 J of energy?
Mechanical energy:
*Assume all energy transfer is complete (100%)
1. The 200 kg hammer of a pile driver is lifted 10 m. Find the gravitational potential energy of the system when the hammer is at this height.
2. A 60 kg shell is shot from a cannon to a height of 415 m.
a. What is the gravitational potential energy of the shell?
b. What is the change in potential energy of the shell when it falls to a height of 200 m?
3. A person has a mass of 45 kg and is moving with a velocity of 10 m/s.
a. Find the person’s kinetic energy.
b. The person’s velocity becomes 5 m/s. What is the kinetic energy of the person?
4. A person and bicycle have a mass of 80 kg together. The person rides the bicycle 1.8 km in 10 minutes at a
constant velocity. What is the kinetic energy?
5. An 8 kg flower pot falls from a window ledge 12 m above a sidewalk.
a. What is the kinetic energy of the pot just as it reaches the sidewalk?
b. What is the velocity of the pot just before it strikes the sidewalk?
6. A 15 kg model plane flies horizontally at 12.5 m/s.
a. Calculate its kinetic energy.
b. The plane goes into a dive and levels off 20.4 m closer to the earth. How much potential energy did it lose
during the dive?
c. How much kinetic energy did the plane gain during the dive?
d. What is the new kinetic energy?
e. What is the new horizontal velocity?
7. During the hammer throw at a track meet, an 8 kg hammer is accidentally thrown straight up. If 784 J of energy
was transferred to the hammer to give it its vertical velocity, how high will it rise?
8. A 10 kg test rocket is fired vertically upward. Its fuel gives it a kinetic energy of 1960 KJ before it leaves the launch
pad. How high will the rocket rise?
9. A 5 kg mass is projected straight up with a velocity of 15 m/s.
a. What is the initial kinetic energy of the mass?
31
b. To what height does the mass rise?
10. A racing car has a mass of 1500 kg. What is its kinetic energy in joules if it has a speed of 108 km/h?
11. A 20 kg mass is on the edge of a 100 m high cliff.
a. What potential energy does it possess?
b. The mass falls from the cliff. What is the kinetic energy just before it strikes the ground?
c. What speed does it have as it strikes the ground?
12. A 56 kg diver runs and dives from the edge of a cliff into the water which is located 4 m below. If she is moving at 8
m/s the instant she leaves the cliff, determine the following: a. Her gravitational potential energy relative to the water surface when she leaves the cliff
b. Her kinetic energy when she leaves the cliff
c. Her total mechanical energy relative to the water surface when she leaves the cliff
d. Her total mechanical energy relative to the water surface just before she enters the water below
e. The speed at which she enters the water
13. Complete the missing information.
Effective Forces & Work: 1. The diagrams below show forces acting on various objects. For each case determine the resultant force.
a. b.
10 N 22.5 N 70 N 42 N
c. d.
7.5 N 32 N 1200 N 850 N
e. f.
0.56 N 2.75 N 18 N 12 N
2. Determine the weight for each of the masses.
a. 14 kg b. 0.43 kg
c. 0.7 kg
v = 13 m/s
m = 10 kg
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3. Determine the mass of these weights.
a. 98 N b. 80 N
c. 5.88 N
4. An economy car has a mass of 1000 kg. What is the weight?
5. A small yacht weighs 14 700 N. What is its mass?
6. A 7.5 kg object is placed on a spring scale. If the spring scale reads 78.4 N, what is the acceleration of gravity at
that location?
7. A car has a mass of 1200 kg. How much would the car weigh on the moon? (The moon’s gravitational acceleration
is 1.6 m/s2)
8. A force of 750 N is needed to push a car across a lot. Two students push the car 40 m. How much work is done?
9. How much work is done in lifting a 60 kg crate a vertical distance of 10 m?
10. A person carries a 34 N package form the ground floor to the fifth floor of an office building, or 15 m upward. How
much work does the person do to move the package?
11. What work is done to lift a 49 kg crate a distance of 10 m?
12. Jane is pulling on a rope with a force of 300 N over a distance of 25 m.
Calculate the amount of work done.
13. A 500 N trunk is placed on an inclined plane that forms a 35 angle with the horizontal.
a. Calculate the component parallel to the direction of travel.
b. Calculate the component parallel to the direction of travel if the incline plane is moved to an angle of 60.
c. When the angle of the incline increased, how did the force components acting on the trunk change?
14. A car weighing 12 000 N is parked on a 36 slope.
a. Find the force tending to cause the car to roll down the hill.
b. What is the component perpendicular to the direction of travel.
15. What is the component parallel to the direction of travel needed in order to slide a 325 N trunk down a 20 incline
plane?
Chapter 4
Physical Change: Changes that do NOT modify the nature or characteristic properties of matter
The atoms and molecules of the substance do not change
Examples: Shape State
Crushing Melting (solid liquid)
Pulverizing Evaporation (liquid gas)
Laminations Condensation (gas liquid)
Extrusion Solidification (liquid solid)
Liquefaction (gas liquid)
Sublimation (solid gas)
33
Chemical Change:
Changes that modify the nature AND characteristic properties of matter The bonds between atoms are rearranged and new molecules are formed
Examples: Photosynthesis Carbon dioxide + Water Glucose + Oxygen
(CO2) (H2O) sun (C6H12O6) (O2)
Neutralization Acid + Base Salt + Water
Signs of a Chemical Change: Besides the characteristic properties changing of the newly formed substance, the
following are other signs of a chemical change: o Formation of a gas
Ex: When calcium carbonate was placed in hydrochloric acid, carbon dioxide was produced (we noticed
bubbles during the reaction).
o Formation of a precipitate
Ex: When you mixed sodium hydroxide and calcium chloride (two clear liquids) a white precipitate formed at the bottom of the test tube.
o A permanent change in colour
Ex: When you heated the iron and sulfur mixture (dark grey), you noticed a yellow cloud of smoke and
red-like material forming.
Note: When you heated the iodine you noticed a colour change, but it was easily reversed – an example of sublimation.
o The production of heat and light
Ex: The combustion of the magnesium strip created a bright light that you needed cobalt blue glass to
see it.
Law of Conservation of Mass:
The mass of reactants is equal to the mass of products Regardless of balancing the equation, the masses remain the same
Ex: How much CO2 is needed to completely react?
CH4 + O2 CO2 + H2O CH4 + 2 O2 CO2 + 2 H2O
(8g) + (32g) = (x) +(18g) (8g) + (32g) = (x) + (18g)
Answer: 22 g of CO2 Mass didn’t change after balancing
Balancing Chemical Equations: Balancing a chemical equation consists in placing a coefficient before each reactant and product so that the number
of atoms of each element on the reactant side is equal to the number of atoms of each element on the product side.
o Coefficients must be whole numbers
o Coefficients must be as small as possible
o New substances must never be added, nor existing substances removed
o Subscripts in chemical formulas must never be changed
o The final equation should always be checked by counting the number of atoms of each element on both
sides
Ex: Unbalanced H2SO4 + KOH K2SO4 + H2O
Balanced H2SO4 + 2 KOH K2SO4 + 2 H2O
34
Check
balancing
Reactants Products
H: 2 + 2(1) = 4
S: 1 O: 4 + 2(1) = 6
K: 2(1) = 2
H: 2(2) = 4
S: 1 O: 4 + 2(1) = 6
K: 2
Unbalanced C5H12 + O2 CO2 + H2O
Balanced C5H12 + 8 O2 5 CO2 + 6 H2O
Check
balancing
Reactants Products
C: 5 H: 12
O: 8(2) = 16
C: 5(1) = 5 H: 6(2) = 12
O: 5(2) + 6(1) = 16
EST – Stoichiometry:
Stoichiometry is the study of the quantity of reactants required for chemical reactions to occur and of the quantities
of products that are thus formed.
o The Law of Conservation of Mass states: Mass of reactants = Mass of products
o It can be used to predict the mass of a substance in a chemical reaction.
Four Methods Used:
Type 1: Mole Mole
Ex. 1: How many moles of MgO are produced if 4 moles of magnesium reacts with oxygen gas (O2)?
Step 1: Write & balance equation Step 2: Find # of moles produced
2 Mg + O2 2 MgO 2 mol Mg = 4 mol Mg
2 mol MgO x mol MgO
Answer: 4 moles of MgO produced.
Ex. 2: How many moles of nitrogen gas (N2) are required to make 7.5 mol of ammonia (NH3) if added to hydrogen gas (H2)?
Step 1: Write & balance equation Step 2: Find # of moles produced
N2 + 3 H2 2 NH3 1 mol N2 = x mol N2
2 mol NH3 7.5 mol NH3
Answer: 3.75 moles of N2 needed.
Type 2: Mole Mass
Ex.: How many grams of NaClO3 must be decomposed to produce sodium chloride (NaCl) and 1.65 moles of oxygen gas
(O2)?
Step 1: Write & balance equation Step 2: Find # of moles of NaClO3
2 NaClO3 2 NaCl + 3 O2 2 mol NaClO3 = x mol NaClO3
3 mol O2 1.65 mol O2
x = 1.1 mol NaClO3
Step 3: Find molar mass of NaClO3 Step 4: Find mass of NaClO3
Na: 1 x 22.99 = 22.99 1.1 mol = x grams
Cl: 1 x 35.45 = 35.45 106.41 g/mol O: 3 x 15.99 = 47.97
106.41 g/mol
Answer: 117.051 g of NaClO3.
35
Type 3: Mass Mole
Ex.: How many moles of Li are needed to react with fluorine gas (F2) to make 435 g of lithium fluoride (LiF)?
Step 1: Write & balance equation Step 2: Find molar mass of LiF
2 Li + F2 2 LiF Li: 1 x 6.94 = 6.94
F: 1 x 19.0 = 19.0
25.94 g/mol
Step 3: Find # of moles of LiF Step 4: Find # of moles of Li
n = 435 grams 2 mol Li = x mol Li 25.94 g/mol 2 mol LiF 16.77 mol LiF
n = 16.77 moles of LiF Answer: 16.77 moles of Li.
Type 4: Mass Mass
Ex.: Calculate the mass of sodium hydroxide (NaOH) that neutralizes 14.7 g of sulphuric acid (H2SO4) to produce sodium
sulphate (Na2SO4) and water.
Step 1: Write & balance equation Step 2: Find molar mass of H2SO4
2 NaOH + H2SO4 Na2SO4 + 2 H2O H: 2 x 1.01 = 2.02
S: 1 x 32.07 = 32.07
O: 4 x 15.99 = 63.96 98.05 g/mol
Step 3: Find # of moles of H2SO4 Step 4: Find # of moles of NaOH
n = 14.7 grams 2 mol NaOH = x mol NaOH
98.05 g/mol 1 mol H2SO4 0.15 mol H2SO4 n = 0.15 moles of H2SO4 x = 0.3 moles of NaOH
Step 5: Find molar mass of NaOH Step 6: Find mass of NaOH
Na: 1 x 22.99 = 22.99 0.3 mol = x grams O: 1 x 15.99 = 15.99 39.99 g/mol
H: 1 x 1.01 = 1.01 39.99 g/mol
Answer: 12 grams of NaOH.
EST – Endothermic & Exothermic Reactions:
Endothermic Reactions:
An endothermic reaction is a chemical change that absorbs energy.
Exothermic Reactions:
An exothermic reaction is a chemical change that releases energy.
Calculating Reaction Energy:
The amount of energy released or absorbed by a reaction can be estimated by calculating its reaction energy, which
is the difference between the energy absorbed when the bonds between the atoms of the reactants break and the energy released when the bonds between the atoms of the products form.
36
Example problems:
a) Ammonia synthesis is a reaction that is widely used in industry. Calculate the
reaction energy of the process in order to estimate the amount of energy
released or absorbed.
b) Refer to Tables 4.12 and 4.13 on page 115 of your student book to answer the following questions about the
combustion of acetylene, a gas used in welding.
The unbalanced equation for the combustion of acetylene is:
C2H2 + O2 CO2 + H2O
The bond structures are:
H–CC–H + O=O O=C=O + H–O–H
Calculate the reaction energy of this reaction.
Types of Chemical Changes:
Acid-Base Neutralization:
(Na+ + OH-) + (H+ + Cl-) (Na+ + Cl-) + (H+ + OH-)
The hydroxide ion and hydrogen ion reform and
bond to form WATER
SALT WATER
The sodium ion and
chlorine ion reform a bond to form the SALT
Energy absorbed by the reactants: 946 kJ + (3 435 kJ) = 2251 kJ
Energy released by the products: 6 389 kJ = 2334 kJ
Reaction energy = 2251 kJ – 2334 kJ = –83 kJ
The reaction releases 83 kJ of energy.
The balanced equation is: 2 C2H2 + 5 O2 4 CO2 + 2 H2O
Energy of the bonds:
Reactants: 2 triple bonds CC: 2 741 kJ = 1482 kJ
4 bonds C–H: 4 414 kJ = 1656 kJ
5 double bonds O=O: 5 498 kJ = 2490 kJ
Total for the reactants = 5628 kJ
Products: 8 bonds C=O: 8 741 kJ = 5928 kJ
4 bonds O–H: 4 464 kJ = 1856 kJ
Total for the products = 7784 kJ
Reaction energy = Energy absorbed – Energy released = 5628 kJ – 7784 kJ = – 2156 kJ
The reaction released 2156 kJ of energy.
Reaction:
37
Combustion:
Combustion is a form of oxidation that releases a large amount
of energy. Three conditions must be fulfilled for combustion to take place:
o An oxidizing agent (oxygen source)
o A fuel
o The ignition temperature (heat source)
Combustion is categorized as:
o Rapid combustion – short period of time & releases a
great amount of heat & light (ex: a campfire)
o Spontaneous combustion – unpredictable with disastrous consequences (ex: forest fire)
o Slow combustion – a long period of time & releases energy gradually into the environment (ex: respiration,
rust)
Cellular Respiration & Photosynthesis:
Cellular respiration is a chemical change in which glucose (C6H12O6)
and oxygen (O2) are used to generate energy. The reaction also
produces carbon dioxide (CO2) and water (H2O).
Photosynthesis is a chemical change that produces glucose (C6H12O6)
and oxygen (O2) from solar energy, carbon dioxide (CO2) and water (H2O).
EST – Nuclear Transformations:
Nuclear stability refers to the state of a nucleus in which the nuclear force geater than the forces of electrical
repulsion between protons.
The stability of the nucleus depends on two factors: its size and the number of neutrons it contains.
Radioactivity is a natural process in which an unstable atom spontaneously transforms into a more stable atom, or
several more stable atoms, while releasing energy in the forms of radiation.
The half-life is the time it takes for half of the nuclei in a sample of radioactive material to decay.
38
Nuclear Fission:
Nuclear reaction in which the nucleus of a large atom is split to form two
or more lighter atomic nuclei.
Nuclear Fusion:
Nuclear reaction in which two small atomic nuclei join together to form
one heavier nucleus. Examples:
a) The reaction involves fission because the products have smaller nuclei than the reactant.
U + n Xe + Sr + 2 n
b) The reaction involves fusion because the product has a larger nucleus than the reactants.
H + H He + n
Exercises: Physical & Chemical Changes:
1. From the list of changes below:
a. Indicate whether each change is chemical (C) or physical (P).
b. Explain how you were able to identify the chemical changes. 1. Logs burning in a campfire.
2. A sheet of paper being crumpled. 3. Limewater clouding when brought into contact with carbon dioxide.
4. Cream separating from milk.
5. Metal rusting. 6. Paint peeling.
7. Leaves decomposing. 8. Beer fermenting.
9. Salt dissolving in water.
10. Snow melting.
2. What physical changes could produce the following results? a. When I open a bottled soft drink, it fizzes.
b. The level of water in a pool tends to decrease over time. c. The level of mercury in a thermometer varies.
d. In winter, we need to add antifreeze to the car’s radiator.
3. What chemical changes could produce the following results?
a. The production of water and carbon dioxide from food. b. The production of alcohol using simple sugars.
c. The production of energy in a car engine.
d. The action of digestive juices on proteins to separate them into amino acids.
4. State whether each of the following is a chemical or physical change and give a possible cause for the following changes:
a. Water freezing. b. The transformation of wood to ash.
c. Iron rusting.
d. Acidification of lakes and rivers. e. Sublimation of iodine.
5. Distinguish the physical changes from the chemical changes in the following list:
a. A tooth decays.
b. Two solutions are mixed together and the temperature of this mixture rises ten degrees.
1 0
140 54
94 38
1 0
1 0
2 1
2 1
3 2
235 92
39
c. A nichrome wire is heated.
d. A yellow solid is heated, producing a choking odour. e. A sheet of paper is crumpled.
f. A sauce stored in the refrigerator gels. g. In the oven, bubbles form inside a cake.
h. Table salt dissolves in water.
6. List the signs of a chemical change.
a. ______________________________________________ b. ______________________________________________
c. ______________________________________________ d. ______________________________________________
Law of Conservation of Mass: 1. In a reaction involving hydrochloric acid and calcium carbonate, the total mass of the reactants was 11 g. What
would be the mass of the products formed by this reaction?
2. Eight grams of hydrogen reacts completely with 0.4 grams of oxygen according to the equation:
2 H2 + O2 2 H2O
What will be the mass of the water produced?
3. Eight grams of methane (CH4) is burned in 32 grams of oxygen according to the equation:
CH4 + 2 O2 CO2 + 2 H2O
Along with a certain quantity of water, 22 grams of carbon dioxide (CO2) is obtained. What is the mass of water
obtained?
4. Some rockets are fuelled by hydrogen. The reaction that occurs corresponds to the following equation:
2 H2 + O2 2 H2O
What would be the mass of water produced during a rocket launch if 80 kg of hydrogen burned in 640 kg of oxygen?
5. Decomposing organic matter often produces methane gas (CH4). This gas burns to form carbon dioxide and water
according to the following equation:
CH4 + 2 O2 CO2 + 2 H2O
What is the mass of the carbon dioxide produced if 8 g of methane burns in 32 g of oxygen to produce 18 g of water vapour?
6. After neutralizing hydrochloric acid (HCl) with calcium carbonate (CaCO3), a student obtains 11 g of CO2, 27.75 g of CaCl2 and 4.5 g of water. The student began with 25 g of CaCO3 and 25 g of HCl. Once the reaction is completed,
the student notices that while all the CaCO3 was used, there is a little bit of HCl left over. What is the mass of the remaining HCl?
7. What mass of magnesium fluoride (MgF2) is formed when 2.4 g of magnesium reacts with 3.8 g of fluorine according
to the following equation?
Mg + F2 MgF2
8. Calculate the mass of sodium hydroxide (NaOH) that neutralizes 14.7 g of sulphuric acid (H2SO4) in order to produce
21.3 g of sodium sulphate (Na2SO4) and 5.4 g of water. The equation for the reaction is:
2 NaOH + H2SO4 Na2SO4 + 2 H2O
9. What mass, in grams, of calcium carbonate (CaCO3) must react with 165.9 g hydrochloric acid (HCl) in order to
produce 100 g of carbon dioxide gas (CO2), 252.3 g of calcium chloride (CaCl2) and 40.9 g of water?
2 HCl + CaCO3 CaCl2 + CO2 + H2O
10. What mass, in grams, of silver carbonate (Ag2CO3) can form added to 10.1 g of sodium nitrate (NaNO3) in order to
be produced by 12.6 g of sodium carbonate (Na2CO3) and 20.2 g of silver nitrate (AgNO3)?
2 AgNO3 + Na2CO3 2 NaNO3 + Ag2CO3
40
11. What mass, in grams, of ammonia (NH3) is expected to form when 6 g of hydrogen gas (H2) combines with 28 g of
nitrogen gas (N2)?
N2 + 3 H2 2 NH3
Balancing Equations:
1) __Cu + __O2 __CuO
2) __Zn + __HCl __ZnCl2 + __H2
3) __P + __H2 __PH3
4) __Al + __CuSO4 __Cu + __Al2(SO4)3
5) __H2SO4 + __Al __H2 + __Al2(SO4)3
6) __Na + __H2O __H2 + __NaOH
7) __NH3 + __O2 __NO2 + __H2O
8) __Na2CO3 + __H3PO4 __Na3PO4 + __CO2 + __H2O
9) __FeS + __O2 __Fe2O3 + __SO2
10) __Na2CO3 + __FeCl3 + __H2O __Fe(OH)3 + __NaCl + __CO2
11) __P2O5 + __H2O __H3PO4
12) __H3PO4 + __KOH __K3PO4 + __H2O
13) __H2 + __O2 __H2O
14) __HCl + __NaOH __NaCl + __H2O
15) __Na + __NO3 __Na2O + __N2
16) __C + __S8 __CS2
17) __Na + __O2 __Na2O
18) __N2 + __O2 __N2O5
19) __H3PO4 + __Mg(OH)2 __Mg3(PO4)2 + __H2O
20) __NaOH + __H2CO3 __Na2CO3 + __H2O
21) __KOH + __HBr __KBr + __H2O
22) __H2 + __O2 __H2O2
23) __Na + __O2 __Na2O
24) __Al(OH)3 + __H2CO3 __Al2(CO3)3 + __H2O
25) __NH4OH + __H3PO4 __(NH4)3PO4 + __H2O
Types of Chemical Changes:
1. What type of reaction does each of the following examples describe?
a) 2 HI(aq) + Ba(OH)2 BaI2(aq) + 2 H2O(l)
b) sugar that reacts with oxygen and releases energy
2. Complete each of the following acid-base neutralization reactions and balance the equations.
a) 2 HCl(aq) + Mg(OH)2(aq)
b) HNO3(aq) + KOH(aq)
c) HBr(aq) + NaOH(aq)
3. What type of reaction does each of the following examples describe?
a) You mix an acid with a base and obtain a pH of 7. b) Plants produce oxygen.
c) You maintain a certain body temperature. d) Bananas turn black when left in the open air.
41
e) You set off fireworks at a party.
f) Hot weather causes a forest fire. g) An old boat rusts.
4. For each of the following examples of combustion, write the oxidizing agent and the fuel in the appropriate columns.
Example of combustion Oxidizing agent Fuel
Food is digested.
A newspaper catches fire.
Dry hay starts burning in a barn.
EST – Stoichiometry: 1. One of the gasses responsible for acid rain is sulphur dioxide (SO2), which, in the presence of oxygen, transforms
into sulphur trioxide (SO3) as shown in the equation:
2 SO2 + O2 2 SO3
a. What mass of oxygen is needed to oxidize three moles of sulphur dioxide?
b. What mass of sulphur dioxide has been oxidized by oxygen
2. When it reacts with the water vapour in the atmosphere, sulphur trioxide (SO3) transforms into sulphuric acid
(H2SO4), which is a component of acid rain.
SO3 + H2O H2SO4
a. How many moles of water are needed to produce 392 g of sulphuric acid?
b. How many molecules of acid can form if the mass of sulphur trioxide present in the air is 40 g?
3. A container of hydrochloric acid (HCl) spilled on a marble surface. The marble contains calcium carbonate (CaCO3),
which reacts with the acid to produce calcium chloride (CaCl2), carbon dioxide and water.
2 HCl + CaCO3 CaCl2 + CO2 + H2O
a. If 500 ml of 0.2 mol/L acid spilled, what mass of calcium carbonate reacted?
b. How many moles of carbon dioxide were formed during this reaction?
c. How many molecules of water were formed during this reaction?
4. The light given off by a flash bulb is part of the energy released by the combustion of a magnesium filament in an
oxygen medium. The white powder produced is magnesium oxide (MgO).
2 Mg + O2 2 MgO
a. If the magnesium strip had a mass of 0.12 g, what mass of magnesium oxide was produced?
b. How many molecules of oxygen would the flash bulb have to contain to produce this reaction?
c. If the flash bulb contained 0.64 g of oxygen, how many moles of magnesium could burn?
d. What mass of magnesium oxide would be formed under those circumstances
5. What mass of oxygen is needed for the combustion of 8 g of methane given the following equation?
CH4 + 2 O2 CO2 + 2 H2O
6. Calculate the mass of aluminum is needed to combine with 84 g of calcium oxide (CaO) given the following equation:
3 CaO + 2 Al Al2O3 + Ca
42
7. One way to produce iron in a smelting furnace is to create a reaction between iron ore (Fe2O3) and carbon monoxide
(CO). This reaction transforms the carbon monoxide into carbon dioxide and releases the iron according to the equation:
Fe2O3 + 3 CO 3 CO2 + 2 Fe
a. How many moles of carbon dioxide molecules are formed if the iron ore contains 15 moles of Fe2O3?
b. What mass of carbon monoxide is required to produce five moles of iron atoms?
c. What mass of iron is obtained if the reaction releases 1320 g of carbon dioxide?
d. How many carbon monoxide molecules does it take to produce four moles of iron?
e. If 1.2x1024 molecules of Fe2O3 react, what mass of carbon dioxide will form?
EST – Endothermic & Exothermic Reactions:
1. Is each of the following reactions endothermic or exothermic? Explain your answers.
A. When a certain amount of potassium nitrate is dissolved in water, the water temperature drops from 23°C to 18°C.
B. Jack cooks himself a steak.
C. When cold water is mixed with sulphuric acid, the mixture can rapidly reach the boiling point of water.
D. A flare burns up slowly.
Endothermic reactions:
Exothermic reactions:
2. Refer to Tables 4.12 and 4.13 on page 115 of your textbook to answer the following questions about the combustion of
acetylene, a gas used in welding.
The unbalanced equation for the combustion of acetylene is:
C2H2 + O2 CO2 + H2O
The bond structures are:
H–CC–H + O=O O=C=O + H–O–H
a) Calculate the reaction energy of this reaction.
b) What amount of energy is needed to start this reaction?
c) What amount of energy is released during the formation of new bonds?
d) How many grams of acetylene are needed for a welding task that takes 4832 kJ of energy?
3. Julie has inherited her grandfather’s old cottage on a lake. There are five well-maintained cottages around the lake,
which is approximately 1.0 km long and 500 m wide. Quiet and secluded, the lake is 2.0 km from the nearest road. To get to the cottage, Julie must go by foot or all-terrain vehicle. There is no electricity; Julie’s grandfather used a
wood-burning stove for heating and cooking. He enjoyed chopping wood, but Julie does not, so she wants to install gas for heating, lighting and cooking. Since she must consider the mass of gas to be transported, she is hesitating
between propane and natural gas. A friend told her that whichever gas she uses, she will obtain the same amount of
energy for the same mass of fuel burned. Is Julie’s friend right? Do these two fuels produce the same amount of energy for the same mass of gas burned? Show your calculations for 704 g of burned gas, using the following
chemical equations:
Natural gas: CH4 + 2 O2 CO2 + 2 H2O + 892 kJ
Propane: C3H8 + 5 O2 3 CO2 + 4 H2O + 2233 kJ
EST – Nuclear Transformations:
Technetium (Tc) is element 43 in the periodic table. It took a long time to isolate this element because it occurs very rarely in nature. Between 1830 and 1930, many scientists thought they had found it, but subsequent analyses of their samples
revealed that all traces of it had disappeared. In 1937, Perrier managed to isolate a sample of technetium 97. Scientists then
43
began to produce technetium 99 artificially by bombarding molybdenum (Mo). They soon observed that the element, though
light, is radioactive. Technetium 99 is widely used in medical imaging because of its short half-life, which saves patients needless radiation. It has also been observed that 88.5 percent of technetium decay takes the form of gamma rays. As a
result, only a small number of penetrating particles are emitted, and the living tissues being treated absorb less energy. Technetium has become essential to medical imaging, especially in the identification of sentinel lymph nodes in breast cancer
treatment. The Chalk River reactor in Ontario provides two thirds of global technetium production. For each kilogram of
uranium the reactor uses, one nanogram (10–9 g) of technetium is produced.
a) Explain the radioactivity of technetium, referring to nuclear forces. b) Why is it surprising that technetium is a radioactive element?
c) The text contains the following sentence: “As a result, only a small number of penetrating particles are emitted, and the living tissues being treated absorb less energy.” Which particles may be absorbed to a greater extent by tissues and thus be harmful to the body?
d) Vicky, a breast cancer patient, was hospitalized on June 2 to receive a technetium treatment. At 4 p.m. she received a 12-mg dose of technetium. Radiation levels around the patient are considered negligible when only 1.5 mg of the radioactive substance remain in her body. At what specific date and time will Vicky be able to leave the hospital and go back home?
e) Which type of nuclear transformation do you think is used at the Chalk River power plant? Explain your answer.
CHAPTER 5
Electricity & Electrical Charges:
Electricity describes all the phenomena caused by positive and negative charges.
Electrical charge is a property of protons and electrons. A proton carries a positive charge, while an electron carries
a negative charge. o A negatively charged body contains more electrons than protons
o A positively charged body contains fewer electrons than protons
Electrically charged matter has revealed: o Electrical charges of like signs (two positive or two negative charges) repel each other
o Electrical charges of opposite signs (one positive and one negative charge) attract each other
Insulator:
An insulator is a substance that impedes the free flow of electric
charges.
o Electricity doesn’t flow easily
Semiconductors:
Material with electrical conductivity between that of conductors and insulators,
allowing it to control the amount and direction of current flowing through it.
They are widely used in electronics, particularly in the manufacture of transistors
Conductors:
A conductor is a substance that permits the free flow of electrical charges. o Electricity flows easily
Conductivity of connecting wires depends on the following factors:
o Nature (type) of the substance the wire is made of: Gold is the best conductor
Copper is excellent, whereas nichrome is poor
Insu
lato
rs Wood, Rubber,
Glass, Ebonite, Mica,
Sulphur, Dry air, Ceramic, Plastic, etc.
Se
mi-
co
nd
ucto
rs Germanium, Silicon,
Cotton, Wool,
Marble, Sand, Paper, Ivory, Most air, etc.
Co
nd
ucto
rs Copper, Silver, Gold,
Aluminum and all other metals, Water,
acids, Metallic salts, Graphite, Human
body, etc.
44
o Diameter of wire:
The greater the diameter, the more conductive Gauge numbers:
Used to classify the thickness of connecting wires
The higher the gauge, the smaller the diameter
o Length of wire:
The shorter the wire, the more conductive
o Temperature of wire:
The lower (colder) the temperature, the more conductive
Static Electricity:
Static electricity describes all the phenomena related to electrical charges at
rest.
An object can be charged by:
o Friction
Two neutral objects rubbed together Friction pulls electrons away one object and transfers them to
another. Two objects result in opposite charges
o Conduction
One charged object and one neutral object come into contact
The charge of one object is shared between two objects when they come into contact Two objects with like charges
o Induction
One charged object and one neutral object come into contact The proximity of the charged object causes the charges in the neutral object to separate
One charged object and one object carrying a partial positive charge on one side and a partial negative charge on the other side
EST – Coulomb’s Law:
Coulomb’s Law states that the magnitude of the force between two immobile and electrically charged particles is
directly proportional to the product of their charges and inversely proportional to the square of the distance between
them.
Fe Electrical Force (N)
k Coulomb’s Constant (9x109 Nm2/C2)
q1 Charge of the first particle (C)
q2 Charge of the second particle (C)
r distance between the two particles (m)
Fe = kq1q2 r2
45
0
1
2
3
4
5
6
7
8
9
0 5 10 15 20 25
Potential Difference (V)
Cu
rren
t In
ten
sit
y (
A)
How to Calculate Conductance:
G = I G = 1 G Conductance (S)
V R I Current Intensity (A)
V Potential Difference (V)
R Resistance ()
Example: Calculate the conductance of a circuit with an intensity of 3 A and a potential difference of 12 V.
G = 3 A
12 V G = 0.25 S
Conductance can also be calculated graphically:
Find the slope of the line:
G = I
V
Example:
G = (8 – 0)
(20 – 0)
G = 0.45 S
Dynamic Electricity:
Dynamic electricity describes all the phenomena related to electrical charges in motion
Electric circuits have both insulators (plastic coating on wires) and conductors (copper wires)
This is so that electricity flows only through selected parts of the circuit
Electrical Symbols:
Electrical Symbol Name Unit Measures…
Lamp or Light N/A N/A
Battery or Power Supply N/A N/A
Switch N/A N/A
Ammeter Ampere or Amp (A) Current Intensity (I)
Voltmeter Volt (V) Potential Difference (V or U)
Resistor Ohm () Resistance (R)
Electrical Current – Current Intensity:
Electrical current is the orderly flow of negative charges carried by electrons
The conventional current direction is the direction in which a positive particle would flow in an electrical circuit o The direction goes from the positive terminal of the power supply to its negative terminal
Current intensity is the number of charges that flow past a given point in an electrical circuit every second
How to calculate current intensity:
I = Q I Current intensity (A)
t Q Charge (C – coulombs)
t Change in time (s)
46
Example: The data sheet for a car headlight indicates that the light requires a current of 15 A. What charge is
needed for one minute of operation?
15 A = Q
60 s
Q = 900 C Potential Difference:
The potential difference is the amount of energy transferred between two points in an electrical circuit
The energy of one joule per coulomb of charge How to calculate potential difference:
V = E V Potential difference (V)
Q E Energy (J)
Q Charge (C)
Example: Electrical circuits in homes usually supply a potential difference of 120V. How much energy is needed to provide a charge of 200 C?
120 V = _E_
200 C E = 240 000 J
Resistance:
Electrical resistance is the ability of a material to hinder the flow of electric
current How to calculate resistance:
R = V R Resistance (Ω)
I V Potential difference (V)
I Current Intensity (A)
Resistance of connecting wires depends on the following factors:
o Nature (type) of the substance the wire is made of:
Poor conductors resist current flow more than good
conductors Nichrome is a better resistor than copper
o Diameter of wire:
The smaller the diameter, the more resistant
o Length of wire: The longer the wire, the more resistant
o Temperature of wire:
The higher (warmer) the temperature, the more resistant
Ohm’s Law is used to calculate resistance:
o States that for a given resistance, the potential difference in an electrical circuit is directly proportional to the
current intensity.
Electrical Power:
Electrical power is the amount of work an electrical device can perform per second
How to calculate power:
P = E P Power (W – watt or kW - kilowatt) P = IV
t E Energy or Work (J or kWh)
t Change in time (s)
I Current Intensity (A)
V Potential Difference (V)
Example 1: Calculate the power of an appliance that has a rating plate reading 10 A and 120 V. P = (10 A)(120 V)
P = 1200 W
47
Example 2: Calculate the time it takes a 100 Watt light bulb to use 4800 J of energy.
100 W = 4800 J
t
t = 48 s
Example 3: How much energy does a 1200 W microwave use for 3 hours a day for a week?
1.2 kW = __E__ 21 h
E = 25.2 kWh
Note: In Hydro Quebec questions, power is in kilowatts (kW) and energy is in kilowatthours (kWh) Electrical Circuits:
An electrical circuit is a network in which electrical charges can flow continuously in a loop.
All circuits contain at least the following components:
o A power supply Total potential difference
o One or more elements that use electrical energy
Light bulb, resistor
o Wires that carry the charges from the power supply to the elements and back
o Ammeters and voltmeters can also be included
To measure the potential difference and current intensity of specific elements
Series Circuits:
A series circuit is a circuit in which the elements are connected end to end.
If one of the components of the circuit is defective, the entire circuit stops working
The energy used by the resistors adds up with each new resistor
o This reduces the amount of energy available (ex. the lights get dimmer – less bright)
Fuses and circuit breakers provide protection in circuits from overload
o They must be installed in series so that the current will be cut off
Parallel Circuits:
A parallel circuit is a circuit that contains at least one branch.
If one of the components of the circuit is defective, the element in other branches continues
functioning. The effect of each resistor is shared among the various pathways
o The total resistance drops as resistors are added
Current intensity is shared among the various resistors
o The demand of the current increases which increases the risk of overload
o A fuse or circuit breakers are installed to protect the devices
EST – Rules for Series & Parallel Circuits (Kirchhoff’s Laws):
Series Circuits:
o Total Resistance (RT) or Resistance Equivalence (REq) RT = R1 + R2 + R3 …
o Total Current Intensity IT = I1 = I2 = I3 …
Current remains the same in a series circuit
o Total Potential Difference VT = V1 + V2 + V3 …
Parallel Circuits:
o Total Resistance (RT) or Resistance Equivalence (REq) 1/RT = 1/R1 + 1/R2 + 1/R3 …
o Total Current Intensity
IT = I1 + I2 + I3 …
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o Total Potential Difference
VT = V1 = V2 = V3 … Potential Difference remains the same in a parallel circuit
Magnetism:
The Earth has a magnetic field to protect and reflect the tons of
radiation (solar flares) emitted.
Magnetism is the property that makes certain materials attract or
repel
Magnetic phenomena are responsible for:
o Speakers in sound systems o Computers, televisions, phone handsets
o Lose radio signals when you drive by power lines o Aurora Borealis (Northern lights)
o Alarm systems, compasses, car components, medical equipment
Key terms:
o Magnetic: A substance that exhibits properties of magnetism
Loadstone, magnetite
o Ferromagnetic: A substance that becomes magnetic temporarily, as long as it remains in the presence of a magnet
Iron, nickel, cobalt, steel
o Non-magnetic: A substance that is completely unaffected by magnets Plastic, wood, glass, aluminum, paper
Magnetic field lines of a bar magnet
Attraction and repulsion
o Like poles repel o Opposite poles attract
Electromagnetism:
Electromagnetism describes all the phenomena resulting from the interaction between electricity and magnetism
First Right Hand Rule:
o Straight line conductor or live wire The thumb of your right hand point in the direction of the current flow (from + to -)
The fingers of your right hand will wrap around the wire in the direction of the magnetic field lines
South Magnetic Pole
North Magnetic Pole
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EST – Second Right Hand Rule:
o Solenoid (or electromagnet): Coil of conducting wire carrying electricity
o A solenoid acts like a bar magnet Your fingers wrap around the coil in the direction of the current flow (from + to -)
Your thumb points in the direction of the magnetic field lines (points North)
o Factors that affect the strength of an electromagnet Core material
Iron, cobalt, nickel
Current Intensity
The higher the current intensity, the stronger the electromagnet
Number of loops of magnet wire (insulated wire) The higher the number of loops, the stronger the electromagnet
First Right Hand Rule Second Right Hand Rule
Note: Solenoid acts like a bar magnet
Thumb: Direction of current (from + to -)
Fingers: Wrap in direction of magnetic field
Thumb: North
Fingers: Direction of current (from + to -)
Exercises: Conductors & Insulators:
1. What is a conductor?
2. What is an insulator?
3. Are the following items more likely to be conductors or insulators?
Conductor Insulator Conductor Insulator Conductor Insulator
Conductor Insulator Conductor Insulator Conductor Insulator
Conductor Insulator Conductor Insulator Conductor Insulator
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4. You are asked to build a circuit that consists of a battery, wire & light bulb. You want the light bulb to shine as
bright as possible. Which of the four possibilities would be the best wire to use? a. A nichrome wire that is 3 m long
b. A nichrome wire that is 2 m long c. A copper wire that is 5 m long
d. A copper wire that is 1 m long
5. Choose which wire would have the best conductance.
a.
c.
b.
d.
6. Which of the following wires shows the best conductivity?
a.
c.
b.
d.
7. On a lab exam, you are asked to choose which of the following substances are insulators. Which of these substances would you choose?
Tap water
Iron
Plastic
Copper
Rubber
8. Complete the statement below. In order for a wire to have the best conductivity, it must be _______________, _______________,
__________________, and the temperature should be ________________.
9. How do engineers use conductors in products and appliances?
10. How do engineers use insulators in products and appliances?
Dynamic Electricity:
1. An electrical appliance has a potential difference of 10 V and a current intensity of 2 A. Calculate its resistance.
2. A circuit has a resistance of 10 and a potential difference of 20 V. Calculate its current intensity.
3. If a circuit has resistance of 25 and a current intensity of 5 A, what does the potential difference measure?
4. An electrical appliance has a circuit which has a resistance of 10 and a potential difference of 5V. What is the
circuit’s current intensity?
5. If a circuit has a current intensity of 10 A and a potential difference of 60 V, what is its resistance?
6. You are building electrical circuits in the lab. You are asked to build a circuit with a current intensity of 100 A and a
potential difference of 25 V. What will be the circuit’s resistance?
7. You are a very curious science student and decide to take apart your toaster. You conduct several tests on the toaster and discover that it has a potential difference of 40 V and a current intensity of 0.01 A. What is the
resistance of the toaster?
Answer: _______________________________________________
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8. During a lab exam, you are asked to build a circuit with a resistance of 20 and a current intensity of 0.2 A. You
then insert a voltmeter to measure the potential difference. What will be the reading on the voltmeter?
9. Your wonderful, intelligent and funny science teacher asks you to demonstrate how to build a circuit in front of your
class. You build a circuit with a resistance of 30 and a potential difference of 90 V. You then demonstrate how to
get the circuit’s current intensity by inserting an ammeter. What will be the reading on the ammeter?
10. You are working in the science lab building electrical circuits. You build a circuit with a current intensity of 3 A and a
resistance of 4 . Another student (a very annoying student) decides to fool around with the electrical circuit you’ve
just built, and touches the wires. The student gets a shock. How much voltage (i.e. potential difference) caused the “shock”?
11. An electrical circuit has a total potential difference of 5 V and equivalent resistance of 0.5 . What is the total
current intensity of the circuit?
12. The circuit has a total current intensity of 30 A and a potential difference of 6 V. What is the resistance of the circuit?
13. The circuit below has a total potential difference of 2 V and a total current intensity of 0.05 A. What is the circuit’s resistance?
14. During a lab exam, you are asked to build a circuit with a resistance of 60 and a current intensity of 0.02 A. Once
constructed, you insert a voltmeter to obtain the potential difference of the circuit. The voltmeter reads 12 V. At
first this value seems correct, but as you continue with your calculations, you realize that you’ve made a mistake.
You study the circuit you’ve built and realize that you’ve used the wrong resistor (you did not use the 60 resistor).
If the current intensity is 0.02 A and the potential difference is 12 V, what is the value of the resistor that you need?
15. You are reviewing for your June exam. You come across a question that asks you to calculate the current intensity
of a circuit that has a potential difference of 15 V and a resistance of 6 . You are excited because you are
confident on these types of questions. After carefully doing the calculations, you know the answer! Which current intensity below is the correct answer?
a. 2.5 A b. 0.4 A
c. 90 A d. 11 A
16. A stereo has a power rating of 500 W and is used for 3600 seconds. How much energy was consumed?
17. A stereo plays for 2 hours and 30 minutes and consumes 1 800 000 J of energy. What is the power rating?
18. A fridge has a power rating of 2.4 kW and is used for 24 hours. How much energy was consumed?
19. A stereo has a power rating of 300 W and uses 270 000 J of energy. How long, in minutes, was the stereo played?
20. A stereo has a power rating of 200 W and is used for 45 minutes. How much energy was consumed?
21. A vacuum has a power rating of 0.75 kW and uses 1 350 000 J of energy. How long was the vacuum used?
22. A kettle is used for 5 minutes and consumes 7200 J of energy. What is the power rating?
23. A 1.44 kW clothes dryer is used for two hours at a time, three times a week. How much energy is consumed over a week?
24. An electrical appliance has a voltage of 150 volts and a current intensity of 4 A. What is the power of this appliance?
25. An electrical appliance has a current intensity of 0.2 A and a voltage or potential difference of 9 V. What is the power of this appliance?
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26. A light bulb has a power rating of 60 W and a current intensity of 0.5 A. What is the potential difference or voltage?
27. An electrical circuit has a power rating of 0.125 kW and a potential difference of 25 V. What is the current intensity?
28. You make toast for your breakfast one morning. You notice that the toaster uses 120 V and has a current intensity
of 6 A. If it takes 2 minutes to toast your bread, how much energy did the toaster use?
29. You accidentally leave your bedroom lights on and go off to school. You know the lights use 120 V and have a current intensity of 5.5 A. You are gone for 5 hours. How much energy did the lights use?
30. Which of the following statements describes current intensity?
a. The flow of 1 electron per second
b. The flow of 1 kilojoule of energy per second c. The flow of 1 coulomb per second
d. The amount of energy needed to cause the flow of 1 coulomb per second
31. A stereo that is connected to a 110 V power supply, has a resistance of 50 ohms. This stero is used every morning
in a classroom for “wake up” music for students. How much energy is consumed if it is used for a total of 22 hours in one month.
Series & Parallel Circuits:
1. The electric below consists of 4 resistors and a power supply. What is the potential difference through R3?
2. The following diagram shows a parallel circuit consisting of three resistors. Using the information on the circuit, find
the value of R3?
3. The circuit below consists of three resistors. The power supply provides a current of 0.25 A when the potential
difference is 17.5 V. What is the potential difference through the R3 resistor?
4. The diagram below shows a circuit that consists of three resistors. You are given the information below. What is
the current intensity through resistor R1?
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5. An electric circuit is illustrated below. The power supply is fixed at 120 V. What is the equivalent resistance of this
circuit?
6. A circuit that consists of 3 resistors R1, R2 and R3, is connected in series and illustrated below. The power supply is
fixed at 42 V. Using this information, what is the value of the resistance of resistor R2?
7. Using the circuit below, solve for everything (i.e. current intensity, potential difference and resistance for each part
of the circuit).
8. The circuit to the right is from an electrical appliance. Solve for everything.
9. You constructed the following circuit in the lab. Solve for everything.
10. You are asked to reconstruct the circuit, beside, for a lab exam. Solve for everything.
11. The following circuit was removed from an electrical appliance. Solve for everything.
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12. You and your lab partner constructed the following circuit during a science lab experiment. Solve for the current
intensity passing through R1.
13. Calculate the equivalent resistance (RT) of the circuit.
14. The following circuit consists of three resistors and a power supply. The total current
intensity is 6 A and the equivalent resistance is 1.5 . The third resistor, R3, has a
resistance of 4 and the current passing through R1 is 3 A. Calculate the current
intensity passing through the second resistor, R2.
Mixed Circuits:
1. The following circuit consists of four resistors and a power supply. Given the information from the diagram, what is the Req of the circuit?
2. What is the Req of the following circuit?
3. What is the R of the following circuit if the resistors have the given values:
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4. What is the equivalent resistance for the following circuit?
5. What is the equivalent resistance for the following circuit?
6. A mixed series-parallel circuit is shown below. Calculate the Req for the mixed circuit.
7. Calculate the current intensity passing through R6.
8. Solve for the resistance of the first resistor, R1.
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9. What is the reading on the voltmeter?
10. The following diagram below shows 5 resistors and a power supply of 24 V. What is the current intensity flowing
through resistor R1?
11. Calculate the total current intensity of the mixed circuit below.
Magnetism:
1. Define the term magnetic and give an example.
2. Define a ferromagnetic substance and give an example.
3. Define a non-magnetic substance and give an example.
4. Magnets have two poles – a north pole and a south pole. Complete the following statements.
a. “Opposite poles ___________________”
b. Same or like poles _____________________”
5. In a lab you have a magnetic object, a non-magnetic object and a ferromagnetic object. State whether each
statement is true or false.
a. The magnetic object and ferromagnetic object will attract each other. b. The ferromagnetic object and the non-magnetic object will attract each other.
c. Nothing will happen if the magnetic and non-magnetic objects are brought together. d. If a nickel was brought near the magnetic object, no reaction would occur.
VT = 60 V
R4 = 10 R5 = 20
R1 = 30
R2 = 10
R3 = 20
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6. You have 2 pieces of metal (A & B), an iron nail and a magnet. You carry out the following tests and record your
observations.
Tests Observation
Bring a magnet & metal A together No reaction
Bring a magnet & metal B together Attraction Bring metal A & the iron nail together No reaction
Bring metal B & the iron nail together No reaction
What can you conclude about the 2 pieces of metal? a. Metal A is non-magnetic & metal B is non-magnetic
b. Metal A is non-magnetic & metal B is magnetic c. Metal A is non-magnetic & metal B is ferromagnetic
d. Metal A is ferromagnetic & metal B is magnetic
7. You have four objects – A, B, C, D. Two of these objects are magnetic, one is ferromagnetic and the other is non-
magnetic. You carry out the following tests and record your observations.
Test Observations
A & C are brought together No reaction A & D are brought together No reaction
C & D are brought together Repulsion or attraction, depending on how you bring them
together
C & B are brought together Attraction
D & B are brought together Attraction
a. Which object is non-magnetic?
b. Which object is ferromagnetic? c. What would happen if you brought A & B together?
8. Four objects were brought together, two objects at a time. Of these objects, one is magnetic, one is non-magnetic
& the other two are ferromagnetic. The observations are shown below.
Test Observations
A & C Attraction
C & D No reaction A & B No reaction
A & D Attraction
Which object is non-magnetic?
a. A b. B
c. C
d. D
9. Draw the magnetic field lines for the following magnets.
a.
b.
c.
d.
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10. A basic magnet is placed a piece of cardboard. Your teacher places iron filings on top of this cardboard. Which of
the illustrations below depicts what the iron filings would look like?
a.
c.
b.
d.
11. A magnetic field is always produced by a straight magnet. In the diagrams below, which illustrations correctly
represent what a magnetic field would look like?
a.
c.
b.
d.
12. From the diagrams below, choose which one correctly shows a magnetic field around a bar magnet.
a.
c.
b.
d.
13. If a compass was placed at the end of a bar magnet, the needle points in a certain direction depending on whether the bar magnet’s end is north or south. Which of the following diagrams is correct?
a.
c.
b.
d.
14. Various straight line conductors are illustrated below. Label correctly the magnetic field lines for each drawing.
a.
c.
b.
d.
15. The diagrams below illustrate a compass placed beside a straight line conductor. Draw the needle pointing in the
correct direction for each compass shown below.
a.
c.
b.
d.
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16. The figure below represents the Earth, which is a large magnet. Complete the figure with the following terms.
– geographic North Pole
– North Magnetic Pole
– geographic South Pole
– South Magnetic Pole
17. The circles below represent compasses. In each situation, draw the needles of the compasses, using an arrow to
show the direction they point. a. b.
18. Draw the magnetic field of each of the magnets below.
a.
b.
19. Four electromagnets are shown below. Which electromagnet produces the strongest magnetic field?
a.
c.
b.
d.
20. Four electromagnets with the same core material are shown below. Which electromagnet produces the strongest magnetic field?
a.
c.
b.
d.
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21. Four electromagnets with the same core material are shown below. Which electromagnet produces the strongest
magnetic field? a.
c.
b.
d.
22. Which of the following factors does not affect the strength of an electromagnet’s magnetic field? a. Current intensity
b. Core amterial
c. Current direction d. Number of turns
23. Arrange the following electromagnets in decreasing order of their magnetic fields (i.e. strongest to weakest)
1.
3.
2.
4.
a. 4, 3, 2, 1
b. 1, 3, 2, 4 c. 1, 2, 3, 4
d. 3, 4, 1, 2
24. You enjy working with electronics. One day you decide to take apart your house’s doorbell. You decide to increase the strength of the magnetic field of the electromagnet found in the doorbell. State three ways that you could
achieve this.
25. For your physical science lab exam, you are presented with four electromagnets with iron cores. You are asked to
analyze the strength of their magnetic fields. You carefully observe the electromagnets & record the properties below.
Electromagnet Number of Turns Current Intensity
1 6 4 A
2 10 0.5 A
3 4 3 A
4 2 10 A
Instantly you know which electromagnet is strongest. Rank the electromagnets from weakest to strongest.
61
TECHNOLOGICAL
WORLD
62
CHAPTER 12
Constraints & Deformations:
Constraint describes the effect of forces on a material
Type of Constraint Description Symbol Example
Compression When a material is subjected to forces that tend to
crush it
Squeezing a
sponge
Tension When a material is subjected to forces that tend to
stretch it
Playing tug of
war
Torsion When a material is subjected to forces that tend to
twist it
Wringing a wet
towel
Deflection When a material is subjected to forces that tend to
bend it
Fish bending a
fishing rod
Shearing When a material is subjected to forces that tend to
cut it
Scissors cutting
paper
Depending on the constraint of an object, three types of deformation can occur
o Elastic – constraint leads to a temporary change in the shape or dimensions of the material. When the constraint is removed, the material returns to the original shape.
o Plastic – The constraint leads to a permanent change in the shape or dimensions of the material. Even when the constraint is removed, the material remains deformed.
o Fracture – The constraint is so intense that the material breaks
Properties:
Mechanical properties of a material describe how it reacts when subjected to one or more constraints
Property Description
Hardness Ability to resist indentation or abrasion
Elasticity Ability to return to their original shapes after undergoing a constraint
Resilience Ability to resist shocks without breaking
Ductility Ability to be stretched without breaking
Malleability Ability to be flattened or bent without breaking
Stiffness Ability to retain their shapes when subjected to various constraints
Other properties must also be taken into account to determine the appropriateness/purpose of the material
Property Description
Resistance to
corrosion
Ability to resist the effects of corrosive substances (such as water, various salts and
some components of fumes), which cause the formation of rust, for example
Electrical conductivity
Ability to carry an electric current
Thermal
conductivity Ability to transmit heat
Degradation & Protection:
Degradation of a material is the decline in some of its properties due to the effects of the surrounding environment
o Example: Gardening shears that have rusted because of prolonged exposure to moisture
The protection of a material is the application of procedures that prevent or delay its degradation
o Example: Protect the blades of the gardening shears with oil or grease to prevent the penetration of
moisture
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Categories of Materials & Their Properties:
Wood & Modified Wood (Trees) o Properties
Hardness
Elasticity
Resilience Toughness
Low thermal & electrical conductivity
Ease it can be shaped & assembled
Colours & shade Lightness
o Degradation & Protection
Examples of causes of degradation: Many fungi, microorganisms & insects can infest the wood, feed off it &cause it to rot
Examples of means of protection: Can be varnished, painted or treated with protective coatings. It can be treated by dipping it in an alkaline solution containing copper or by heating it to a high
temperature
Ceramics (Heated inorganic raw materials usually containing oxides) o Properties
Low electrical conductivity Low thermal conductivity
High degree of hardness
Corrosion resistance Heat resistance
Resilience
o Degradation & Protection Examples of causes of degradation: The action of certain acids & bases; thermal shock
Examples of means of protection: Exposure to acids, bases or thermal shocks should be avoided
Metals & Alloys (Mineral ore) o Properties
Good thermal & electrical conductivity
Malleability Ductility
o Degradation & Protection
Examples of causes of degradation: Oxidation causing corrosion (rust) Examples of means of protection: Coatings & Heat treatments
Plastics (Polymers)
o Types:
Thermoplastic is a plastic that becomes soft enough when heated to be moulded or remoulded and that hardens enough when cooled to hold its
shape
Thermosetting plastic is a plastic that remains permanently hard even when heated
o Degradation & Protection
Examples of causes of degradation: Penetration by a liquid; Oxidation; ultraviolet rays
Examples of means of protection: Waterproof coating; addition of antioxidants (carbon black); Addition of pigments that absorb ultraviolet rays
Composites (Combination of two or more types of materials) o Properties depend upon which materials have been combined together
o Degradation & Protection
Examples of causes of degradation: deformation or fracture of the
matrix or reinforcement; loss of adherence between the matrix and the reinforcements
Examples of means of protection: choose materials that are not likely to become deformed or break; assure a strong adherence
between the matrix and the reinforcements
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EST – Technical Drafting:
A projection is the representation of a 3-dimensional object on a 2-dimensional surface
There are two types of projections:
o Isometric: It shows an object in perspective; it represents the 3-dimensions of the
object in a single view
o Multiview: at least 3 views are required to represent the
object in its entirety. It has the advantage of providing
greater detail without distortion
Meaning of the multiview lines:
A—Edge view of a flat or curved surface
B—Intersection of two surfaces (just an edge)
C—Maximum contour of a curved surface
Detail drawings, which specify all relevant manufacturing information, is often included
An exploded view is a drawing in which the various parts of the object are separated from one another
Exercises:
1. In the table below, write the type of constraint described and draw its symbol.
Description Constraint Symbol
1. Sandra and Melanie are going to twist the towel that fell in the
water to wring the water out of it.
2. Rachel is stretching the plastic wrap over the bowl of macaroni she
has made.
3. The weight of the snow has bent the metal fence at the bottom of
the yard.
4. Aviation snips can be used to cut sheet metal.
5. A hammer blow has left a mark on the wooden worktable in the
technology workshop.
6. Gerald is finding it difficult to drive a screw through a knot in a wooden plank.
2. Name the property for the description below. a. A material can resist being crushed
b. A material returns to its original shape c. A material keeps its shape when subjected to a strong constraint
d. A material can flatten without the risk of breaking
3. Complete the table below.
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Object Type of material used Reason
Car bumper
Cooking pot
Bicycle frame
4. Look at the drawing below of the motor unit of a motorized
toy.
a. What type of drawing is it?
b. What type of projection was used to make this drawing?
c. How many different parts does the motor unit contain?
CHAPTER 13
Linking:
During the production of technical objects, two or more parts must be linked together. The linking component is the part
or fluid that performs this mechanical function.
Characteristics of Links: 1. Permanent or Removable?
Question: Can the object betaken apart without causing damage to the object? Answer: No – The link is considered permanent Yes – The link is considered removable Examples:
Permanent Removable
A rivet
A nut and bolt
2. Complete (Fixed) or Partial (Moveable)?
Question: Is movement possible between the two parts? Answer: No – The link is considered complete (fixed)
Yes – The link is considered partial (moveable) Examples:
Complete Partial
Screwdriver handle and shaft
Scissors
3. Direct or Indirect?
Question: Do the parts require something else to hold them together? Answer: No – The link is considered direct Yes – The link is considered indirect Examples:
Direct Indirect
Water bottle and cap
Two pieces of wood glued or screwed
together
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4. Rigid or Flexible (Elastic)?
Question: Is the fastener that links the parts together flexible? Answer: No – The link is considered rigid
Yes – The link is considered flexible Examples:
Flexible Rigid
Tupperware lid
Ordinary hinges
Guiding Control: Guiding is the mechanical function performed by any component that controls the motion of one or more moving
parts.
A guiding component or control is a component whose mechanical function is to guide the motion of moving
parts.
Types of Guiding:
There are three main forms of guiding: translational, rotational and helical.
1. Translational guiding ensures the straight translational motion of a moving part.
2. Rotational guiding ensures the rotational motion of a moving part.
3. Helical guiding ensures the translational motion of a moving part while it rotates about the same axis.
Adhesion & Friction of Parts:
Adhesion is the phenomenon by which two surfaces tend to remain in contact with each
other without slipping.
The strength of adhesion between two surfaces depends mainly on five factors:
The nature of the materials in contact o Ex: adhesion between rubber and asphalt differs from that between steel and asphalt
The presence of a lubricant
o Adhesion is reduced in the presence of a lubricant o Ex: a tire won’t adhere to the road if there is an oil spill
Temperature
o Adhesion is reduced with colder temperatures
A TRACK at the top and bottom of the
window frame allows the translational guiding when the window is opened.
The AXLE attached to the bicycle frame guides the wheel in a rotational motion.
SCREW THREADING inside the
frame of the C-clamp control the helical guiding of the threaded shank.
67
o Ex: a tire will have less adhesion in the winter (icy road) compared to the road in the summer
The state of the surfaces in contact o Usually, the tougher the surface, the better the adhesion
o Ex: adhesion of a tire to asphalt decreases with wear
The perpendicular force exerted by one surface on another o Adhesion increases as this force increases
o Ex: it’s more difficult to pull a loaded sleigh than an empty one
In mechanics, friction is a force that resists the slipping of one moving part over another.
Lubrication is the mechanical function performed by any component that reduces friction between two parts.
Motion Transmission Systems:
Motion transmission is the mechanical function of relaying a motion from one part to another without altering the
nature of the motion. A motion transmission system is a set of components that perform the function of transmitting motion.
Type of Component Description
Driver Component Components that receives the force required to activate the system
Driven Component Component that receives the motion and transfers it to another part
Intermediate Component Component located between the driver and driven components. Not all systems
contain an intermediate component.
Characteristics of Motion in Transmission Systems:
Type Direction of Rotation of Components Reversibility
Gear Trains
Alternates from one gear to another. Yes
Chain & Sprocket Systems
Depending on the configuration, identical only for sprockets touching the same side of the chain.
Yes
Worm & Worm Gear Systems
Varies with the direction of the threads on the worm screw
shaft. No
Friction Gear Systems
Alternates from one gear to another. Yes
Belt & Pulley Systems
Depending on the configuration, identical only for pulleys
touching the same side of the belt. Yes
Driver Driven
Intermediate
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Speed Changes in Motion Transmission Systems:
A speed change occurs in a motion transmission system when the driver does not turn at the same speed as the driven component or components.
Speed Change Description Example
Increase
Motion is transmitted from one gear or pulley to a gear or
pulley of smaller diameter
Motion is transmitted from one gear to a gear with less number
of teeth
Decrease
Motion is transmitted from one gear or pulley to a gear or
pulley of larger diameter
Motion is transmitted from one gear to a gear with more
number of teeth
No Change Motion is transmitted between two gears or pulleys of the same
diameter
Motion Transformation Systems:
Motion transformation is the mechanical function of relaying a motion from one part to another while altering the nature of the motion.
Characteristics of Motion in Transformation Systems:
Type Possible Transformation Reversibility
Rack & Pinion Systems
Rotation Translation
or Translation Rotation
Yes
Screw Gear Systems (Type 1)
Rotation Translation No
Screw Gear Systems (Type 2)
Rotation Translation No
Cam & Follower Systems
Rotation Translation No
Slider – Crank Mechanisms
Rotation Translation
or Translation Rotation
Yes
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Exercises:
1. State the four characteristics of links for each item below.
a.
b.
c.
_______________________
_______________________ _______________________
_______________________
_______________________
_______________________ _______________________
_______________________
_______________________
_______________________ _______________________
_______________________
d.
e.
f.
_______________________
_______________________ _______________________
_______________________
_______________________
_______________________ _______________________
_______________________
_______________________
_______________________ _______________________
_______________________
2. State the main type of guiding control for each item below.
a.
b.
c.
____________________ ____________________ ____________________
d.
e.
f.
____________________ ____________________ ____________________
3. State the speed change for each situation below (increase, decrease or no change).
a.
b.
c.
____________________ ____________________ ____________________
(start at small gear) (start at large gear)
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4. Determine the direction & speed change at each gear.
5. Complete each figure below, indicating:
d. the directions in which the driver and driven components of the system rotate.
e. the name of the motion transmission system illustrated.
6. Match the diagram with the system:
Diagram System Diagram System
7. Look at the three motion transmission systems below.
f. In which of these three systems will there be an increase in speed when motion is transmitted from
component A to component B? Explain your answer.
g. In which of these three systems will there be a decrease in speed when motion is transmitted from
component A to component B? Explain your answer.
A
B
C
Gear Direction Speed Change
A
B
C
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CHAPTER 14
Power Supply: Power supply is the electrical function performed by any component that can generate or provide an electric
current in a circuit.
Examples:
Conduction, Insulation & Protection:
Conduction is the electrical function performed by any component that can transmit electric current from one part
of a circuit to another. Insulation is the electrical function performed by any component that prevents an electric current from flowing.
Protection is the electrical function performed by any component that can automatically cut current flow in the event of a power surge.
Examples:
EST – Electrical Resistance:
A resistor is a component designed to limit the flow of electrons through an electrical circuit.
Electrical resistance of a resistor is indicated with a colour code
o How to use the colour coding for resistors:
Control:
Control is the electrical function performed by any component that can open and close a circuit.
Examples:
72
EST – Types of Switches:
Switch # of Contacts that are opened
or closed at a time # of possible paths for
the electrons Diagram
Single-pole, Single-throw
1
1
Single-pole, Double-throw
1
2
Double-pole, Single-throw
2
1
Double-pole, Double-throw
2
2
Transformation of Energy:
The transformation of energy is the electrical function performed by any component that can convert electrical
energy into another form of energy.
Examples:
EST – Components With Other Functions: A capacitor is a device composed of two electrical surfaces
separated by an insulating material. The device can store an electrical charge.
A diode is a device that allows electric
current to flow is only one direction.
Exercises:
1. Complete the table below.
Symbol Meaning Symbol Meaning Symbol Meaning
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2. Identify the electrical function for each.
3. Write the values for each resistor.
R1: R2:
Red Orange Yellow Gold Yellow Red Orange Gold
4. What am I?
a. I am the function that closes or opens a circuit b. I am he type of current traversed by electrons that always move in the same direction
c. I am a power supply that cannot be moved d. I am the function performed by a breaker
e. I am a switch that lets current take two different paths
f. I work with the Sun g. I am a thin board containing an electrical circuit
h. A colour code indicates my value i. I am a device that allows current to flow in only one direction
1) __________________________
2) __________________________
3) __________________________
4) __________________________
5) __________________________
74
EARTH & SPACE
75
CHAPTER 6
The Lithosphere: The lithosphere is the hard shell of the earth, consisting of the crust and the topmost part of the upper mantle
Minerals:
Minerals are solid inorganic substances with clearly defined composition and properties. Geologists classify minerals according to their properties:
Colour:
o Idiochramatic minerals are elements whose chemical composition give them
their colour. o Allochromatic minerals are elements whose impurities give them their colour
Transparency:
o Property by which a mineral allows light to pass through it. Transparent: lets light pass straight through it.
Translucent: lets light pass through it, but can’t see through it. Opaque: no light rays pass through it at all
Hardness:
o Resistance to scratching according to the Moh’s scale
Streak: o Powder trace obtained by rubbing the mineral on a surface of unglazed
porcelain.
To mine minerals, geologists must first locate them and then extract them from the
lithosphere
Ore is rock containing minerals. when the amount and concentration of a mineral in
a particular site are high enough for mining, the mineral layer is then referred to as a
deposit
Once the ore has been extracted, the mineral is separated from the rock in several stages
Rock: Rocks are heterogeneous solids composed of many minerals.
Igneous rocks are formed when magma cools and solidifies
o Intrusive: Cooled in the Earth
o Extrusive: Cooled outside the Earth due to wind and/or water
Sedimentary rocks are formed by the accumulation and compaction of debris
Metamorphic rocks are former igneous or sedimentary rocks that have been transformed by heat or pressure
Like minerals, certain rocks are extracted from the ground to meet human needs
Soil: Soil horizons are differentiated layers running roughly parallel to the surface of the ground
The layers are: Surface Layer or Organic Matter (1); Topsoil (2); Subsoil (3);
Fragmented Parent Rock (4); Unaltered Parent Rock (5)
EST – A soil’s buffering capacity is its ability to resist changes in its pH when acidic or
alkaline compounds are added to it.
Permafrost is ground whose temperature has been 0°C or lower for at least two years
o Consequences of thawing (melting) the permafrost are: Increase in vegetation
Release of greenhouse gases (methane gas (CH4) & carbon dioxide gas (CO2)) from the soil.
Flooding & landslides Unstable infrastructure (buildings & roads)
1
2
3
4
5
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Energy resources in the Lithosphere:
Fossil fuels result from the transformation of organic residue. These energy sources consist of oil, natural gas and
coal
Nuclear energy is the energy stored in the bonds between the particles in the nucleus of an atom
Geothermal energy is the energy that comes from the internal heat of the Earth
Energy resources:
Fossil Energy Renewable or
Non-renewable Advantages Disadvantages
Fossil Energy
(Oil, Gas, Coal) Non-renewable Readily available
Emits pollutants (CO2, SO2, NOx & methane – all responsible for acid
rain & greenhouse gases)
Nuclear Energy
(Uranium) Non-renewable
Requires few resources for a large amount of energy.
Generates few greenhouse
gases.
Risk of nuclear accidents.
Produces a dangerous radioactive waste.
Geothermal Energy Renewable
It is renewable
Produces few greenhouse
gases
Installing it is too expensive.
EST – Soil depletion is the loss of soil fertility
Contamination is the abnormal presence of a harmful substance in an environment
The Hydrosphere: The hydrosphere is the Earth’s outer layer of water, uniting water in all its states: liquid, solid and gas
Inland waters are all the freshwater bodies found
on continents, uniting rivers, lakes and groundwater
A watershed is an area of land in which all inland
waters drain into the same larger body of water
o Factors that affect how water flows in a
watershed are: Topography
Geology Climate
Vegetation Agricultural, Industrial & Urban
Development
Ocean Circulation:
An ocean current is the movement of seawater in a certain direction and is the combined effect of all the currents that move across the oceans.
Surface Currents:
o Mostly wind driven, they move horizontally
Subsurface (Deep) Currents:
o Mostly due to variations in density Temperature:
Temperature can be influenced by depth of the water; the seasons; and latitude
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Cold water is more dense than warm water
Salinity: Salinity of the water can be influenced by heat and droughts; melting of pack ice and
glaciers Salinity is a measure of the amount of salt dissolved in a liquid
Salt water is more dense than freshwater
Thermohaline Circulation:
o It is a huge “conveyor belt” of surface and subsurface currents that moves water all around the world
Cryosphere:
The cryosphere consists of all the frozen water on the Earth’s surface.
Pack Ice (Ice Floes):
o Pack ice is composed of the ice floating on the oceans near the North and South poles
Glaciers:
o A glacier is a mass of ice on land, formed by compressed snow
o An iceberg is a piece of glacier that has broken off into the ocean
Melting of the cryosphere can affect the circulation of oceans – causes a change in water density (temperature
and salinity)
Energy resources in the Hydrosphere: Hydraulic energy is the energy that can be derived from moving water
A hydroelectric dam converts a river’s hydraulic energy into electrical power
Energy resources:
Energy Renewable or
Non-renewable Advantages Disadvantages
Hydraulic (Tidal) Energy (Underwater
turbines)
Renewable
It is renewable
Produces few greenhouse
gases
Installing it is too expensive
Dangerous for maintenance
Hydroelectric Dams Renewable
It is renewable
Produces few greenhouse gases
Destroy ecosystems
Contamination in water from waste
EST – Eutrophication:
Eutrophication is the process by which natural waters lose their oxygen because of an excessive accumulation of organic matter and nutrients. Eutrophication is often a result of use of pesticides, fertilizers, etc. in agricultural practices.
The stages of Eutrophication are:
Pesticides and fertilizers, particularly the phosphorous they contain, promote algae growth.
The bacteria decompose dead algae. They consume large amounts of oxygen during the decomposition process.
The concentration of oxygen starts to fall.
Fish and other living organisms die from the lack of oxygen.
Exercises:
Lithosphere: 1. Find the word that fits each of the following definitions.
a. inorganic solids with well-defined properties
b. sedimentary rock used to make cement
2. Using the Mohs scale, identify the mineral described in each of the following statements. a. I can scratch fluorite and calcite, but feldspar can scratch me.
b. I can scratch all minerals with a number lower than seven, but I can be scratched by corundum.
3. What is the role of microorganisms in the soil?
4. What distinguishes different soil horizons?
78
5. What am I?
a. the most abundant element on the Earth b. two gases that contribute to acid rain
6. Which fossil fuel does not come from marine organisms?
7. Which greenhouse gas is primarily responsible for global warming?
8. How many nuclear power plants are there in Québec?
9. The widespread use of heavy machinery in agriculture compacts the soil and prevents rain from penetrating the earth. How is this harmful to plant growth?
10. Complete the diagram below that shows how acid rain is formed.
Emissions of ____________ (SO2)
and ______________ (NOx) from
________________ and fossil fuel
combustion.
Rainwater
(_____)
Formation of ___________ (H2SO4)
and nitric acid (_______)
Acid rain
Hydrosphere: 1. What term corresponds to each of the following definitions?
a. a structure used to convert the energy from rivers into electrical energy b. a landform, slope or terrain that can affect water circulation
c. the Earth’s “blue” envelope 2. Is thermohaline circulation responsible for the seasons?
3. Can developing hydroelectric energy harm the environment? Give two examples.
4. The following events lead to the eutrophication of a lake. Place them in chronological order. a. Dead algae fall to the bottom of the lake and accumulate there.
b. Bacteria decompose the algae.
c. Algae grow and spread. d. The amount of oxygen in the lake decreases.
e. The lake slowly dies. f. The bacteria consume large amounts of oxygen.
g. Warm water and phosphorus are discharged from a factory into the lake.
5. Healthy aquatic ecosystems depend on three main factors. What are they?
CHAPTER 7
The Atmosphere:
The atmosphere is the layer of air surrounding the earth
Pressure:
Atmospheric pressure is the pressure of the air in the atmosphere.
Factor Variation in the factor Effect
Number of air particles
Increase Atmospheric pressure rises
Decrease Atmospheric pressure falls
Temperature of air particles
Increase Particles move away from one another and the air tends to rise
Decrease A low-pressure area forms
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An anticyclone is an area of atmospheric circulation surrounding a high-pressure centre. The air turns
clockwise in the Northern Hemisphere and counter-clockwise in the Southern Hemisphere.
o Meteorological conditions are clear skies and stable weather (dry & sunny in the summer; cold in winter)
A depression is an area of atmospheric circulation surrounding a low-pressure centre. The air turns counter-
clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. o Meteorological conditions are formation of clouds and precipitation
o A cyclone is a tropical storm characterized by violent winds revolving around an area of low pressure.
EST – Air Circulation:
Atmospheric circulation is the global-scale movement of the layer of air surrounding the Earth.
Winds Location Direction in Northern Hemisphere
Polar easterlies Between a pole & 60th parallel From northeast to southwest
Westerlies Between 60th and 30th parallel From southeast to northeast
Trade winds Between 30th parallel and equator From northeast to south east
Prevailing winds are major atmospheric currents that blow in a given direction according to global patterns of movement.
Cell Location Movement of air
Hadley cell Between equator and 30th parallel
Air over the equator rises into the atmosphere
It gradually cools as it travels toward the 30th parallel
It runs into winds from Ferrel cell, descends and
returns to the equator
Ferrel cell Between 30th and 60th parallel
Part of the air approaching the 30th parallel surges
toward the poles Near the 60th parallel, this air collides with the winds
from the polar cell
The air rises and returns toward the 30th parallel
Polar cell Between 60th parallel and a pole
The temperature of the air drops to its minimum over
the poles
The air sinks to eh Earth and then returns toward the
60th parallel, where it collides with the Ferrel cell The air is forced to rise and return to the poles
Air Masses:
An air mass is a large expanse of the atmosphere with relatively uniform
temperature and humidity. Cold Front is when a mass of cold air meets a mass of warm air
o The warm air rises rapidly above the cold air
o Formation of cumulus (puffy) clouds & a probability of wind and heavy rain
Warm Front is when a mass of warm air meets a mass of cold air
o The warm air rises gently above the cold air o Formation of nimbostratus (light) clouds & a probability of
cloudy weather and showers
Greenhouse Effect: The greenhouse effect is a natural process that allows the Earth to retain some
of the heat it receives from the Sun. • Solar radiation enters the atmosphere & heats the Earth’s surface –
some bounce off the atmosphere.
• Reflected infrared rays are trapped inside the Earth’s atmosphere due to greenhouse gasses – some out of the atmosphere.
Solar Radiation
Reflected
Infrared Rays
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• The greenhouse gases have both natural origins and human activity linked origins (which leads to climate
change). o Carbon Dioxide (CO2)
Natural: Forest fires; Volcanic eruptions; Cellular respiration Human: Combustion of fossil fuels; Clearing of land
o Methane (CH4)
Natural: Digestion in wild animals; Decomposing plants; swamps Human: Digestion in farm animals; Decomposing household waste; manure storage and
management; Distribution of natural gas; Rice farming in paddy fields o Nitrous Oxide (N2O)
Natural: Bacteria in the soil and oceans Human: Applying nitrogen-rich fertilizer; Certain chemical processes
EST – Atmospheric Contaminants: Climate change is the abnormal modification of climatic conditions on Earth, caused by human activity.
Dust and airborne particles, and metals such as mercury, arsenic and lead, from industry can cause respiratory
difficulties and some are toxic to humans. The ozone layer is a part of the atmosphere with a high concentration of ozone molecules, which absorb some of
the ultraviolet rays from the sun.
o Chlorofluorocarbons (CFCs) are the cause the destruction of ozone molecules
Smog is a thick mixture of fog, smoke and atmospheric pollutants.
o Sulphur dioxide (SO2) and nitrogen oxides (NOx) cause smog and also acid rain
The Effect of the Sun & the Moon on the Earth: A tide is the rise and fall of water in the seas and oceans.
It is caused by the gravitational force of the Moon and, to a lesser extent, of the Sun.
High tide and low tide happens twice a day
depending on the position of the moon
Energy resources in the Atmosphere: Wind energy is the energy that can be drawn from the wind.
Solar energy is the energy that comes from the sun in the form of radiation through the atmosphere.
Tidal energy is the energy although obtained from the ebb and flow of tides caused by the Moon; it is actually
part of the Hydrosphere.
Energy Renewable or
Non-renewable Advantages Disadvantages
Wind (turbines) Renewable
It is renewable
Produces few greenhouse gases
Wind is unpredictable
Energy can’t be stored
Visual pollution
Solar Renewable
It is renewable
Produces few greenhouse
gases
Costly system
Amount of energy produced varies
with Sun’s position & cloudy conditions
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Exercises:
Atmosphere: 1. In which layer of the atmosphere does the temperature drop about 6.5°C every 1000 m?
2. Write “high pressure” or “low pressure” to describe the atmospheric pressure in the following situations.
a. atmospheric pressure at high altitude
b. air that warms up c. an increase in the number of collisions between particles
3. Find the term that fits each of the following definitions.
a. clouds that accompany the formation of a warm front b. the direction of the wind in an anticyclone in Québec
4. Complete the illustration below of global atmospheric circulation, and the accompanying legend.
5. The following statements describe how smog forms. Place them in chronological order.
a. Tropospheric ozone is formed.
b. The sun’s rays strike nitrogen oxide (NOx) molecules. c. Tropospheric ozone combines with other atmospheric pollutants.
d. Cars emit nitrogen oxides (NOx) in their exhaust.
6. What atmospheric phenomenon is related to each of the following situations? a. thick fog in a city during a heat wave
b. unbearable heat inside a car in the sun
c. respiratory problems caused by poor air quality d. pollutants like sulphur dioxide (SO2) and nitrogen oxides (NOx)
e. tropospheric ozone that combines with nitrogen dioxide (NO2)
Space:
1. Complete the following sentences, using the words or groups of words in the box below.
• around
• axis
• basin • collision
• depth • difference
• different
• energy
• every day
• expanses of water
• expensive • far
• force of attraction • gravitational force
• high tides
• hydroelectric
• maximum
• meteorite
• no • renewable
• rotation • season
• spring tides
• Sun
• swell out
• tidal energy
• tidal range • tides
• times • turbine
• twice
a) The Moon was apparently formed as a result of a ________________________ between the Earth and a ________________________ as big as the planet Mars. Fragments of the explosion reunited to form the Moon.
The Moon has an approximate diameter of 3476 km. It revolves ________________________ the Earth and also
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rotates on its own ________________________. It takes 27.3 days for the Moon to circle the Earth and the same
amount of time to make a full ________________________.
b) A ________________________ side of the Earth faces the Moon throughout the day because the Earth is spinning as well. The Moon exerts a ________________________ on the bodies on Earth. This force is known as
“________________________.”
c) Gravitational force is responsible for the tides. The ________________________ that face the Moon are attracted
by it and ________________________ toward it. At the same time, the waters on the opposite side of the Earth swell, too. This happens because these waters are less attracted to the Moon than the Earth itself is. The parts of
the world where the water swells are said to be experiencing “________________________,” and the places where there is no swelling are experiencing low tides.
d) The oceans swell ________________________ a day. Consequently, ________________________, there are two high tides and two low tides. The ________________________ is the difference in water levels between high
tide and low tide. It varies with the location and the ________________________. Factors affecting it are the shape of the coastline, the ________________________of the water and the distance of the Moon or the Sun
from the Earth.
e) The ________________________ also affects tides, but its pull is weaker because it is
________________________ from the Earth. When the Sun and the Moon are aligned with the Earth, the tidal range is at its ________________________. These tides are called “________________________.”
f) It is possible to make use of the ________________________ that comes from the force of rising and falling
tides, which is known as “________________________.” To develop tidal energy at a particular site, tidal power
plants must be built. They operate much like the dams in ________________________ plants. When the tide rises, the water fills a huge ________________________. When the tide goes out, the water is held back,
creating a ________________________ in levels between the water in the basin and the seawater. Water in the basin is then released, and it spins a ________________________ that generates electric current.
g) Tidal energy has certain advantages. It is a ________________________ energy source and produces ________________________ greenhouse gas. Furthermore, since the ________________________ when the
tide will rise and fall are easily predictable, the amount of energy available can be kept constant. Developing tidal power also has some disadvantages, however. For example, building plants that can stand up to harsh ocean
conditions is________________________. Also, few sites are suitable for this type of power plant, which must be
able to draw on ________________________ with a range of at least five metres.
CHAPTER 8
Biosphere: The biosphere is the layer around the Earth containing the lithosphere,
hydrosphere, atmosphere and all living organisms interacting within them.
Biogeochemical Cycles: A biogeochemical cycle is a set of processes by which an element passes
from one environment to the next and eventually returns to its original
environment, in an infinite loop of recycling. The processes include:
o Biological (respiration, digestion, etc.)
o Geological (erosion, sedimentation, etc.) o Chemical (combustion, synthesis, etc.)
The biogeochemical cycles are carbon cycle, nitrogen cycle and phosphorus cycle
Carbon Cycle: The carbon cycle is a biogeochemical cycle involving all the exchanges of carbon on Earth. Carbon makes up the tissues
of living organisms.
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Photosynthesis & Respiration. Plants
use solar energy to capture the carbon
dioxide in the atmosphere or water. The carbon dioxide is used to make food
(glucose). When living organisms breathe, part of the carbon dioxide they
have ingested (from herbivores,
carnivores & omnivores) returns to the atmosphere as carbon dioxide. The
portion of the carbon dioxide that isn’t released through respiration is eliminated
in plant and animal waste. The waste is decomposed by organisms called
decomposers, which emit carbon dioxide
and methane in the process. Part of the carbon dioxide dissolved in water reacts
with water molecules and then with calcium, to become calcium carbonate.
This substance enters into the
composition of the shells and skeletons of marine organisms. The calcium
carbonate from the shells and skeletons falls to the ocean floor and accumulates in the sediment, where it changes and finally forms carbonate rock. The
rock is subject to tectonic movement and can eventually be brought back to the surface.
Fossil fuels. When dead organisms fall to the ocean floor, the carbon in them may remain buried in the
sediment. The carbon sometimes changes into fossil fuels (coal & oil) in a process that takes hundreds of millions of years.
Nitrogen Cycle:
The nitrogen cycle is a biogeochemical cycle
involving all the exchanges of nitrogen on Earth. Nitrogen is used to manufacture proteins and DNA.
Nitrogen fixation. Certain bacteria in the
soil or water take the nitrogen from the atmosphere and convert it to ammonia. Some of
the ammonia reacts with hydrogen to form
ammonium.
Nitrification. Bacteria oxidize ammonium
to form nitrites. Other bacteria oxidize nitrites into
nitrates.
Nitrogen absorption by plants and
animals. Plants can draw ammonium and nitrates from soil or water. Vegetation represents the only
source of nitrogen available to herbivores.
Carnivores obtain their nitrogen by eating herbivores and other animals.
Decomposition of waste. Certain
bacteria and fungi break down the nitrogen-containing substances in plant and animal waste.
They produce ammonia, which dissolves and forms ammonium.
Denitrification. Certain bacteria convert nitrates into molecular nitrogen, which returns to the atmosphere.
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EST – Phosphorus Cycle:
The phosphorus cycle is a biogeochemical cycle involving all the exchanges of phosphorus on Earth. Phosphorus is the
basic component of DNA and is involved in the formation of shells, bones and teeth.
Erosion. Naturally occurring phosphorus is mostly
in rocks. The wind and the rain slowly wear away
small amounts of phosphorus from the rock, usually in the form of phosphates.
Absorption by living organisms. Plants can
rapidly absorb the phosphates they need for growth. Herbivores ingest phosphates by eating plants, and
carnivores, in turn, eat herbivores or other animals.
Decomposition of waste. Digested phosphates
are returned in the soil. All animals eliminate phosphates in their feces and urine. Phosphates are
also released when decomposers break down dead
plants and animals.
Proliferation of plankton and sedimentation.
Phosphates from rocks or from animal and
decomposer excretions make their way into the
oceans. Some phosphates promote the growth of plankton – tiny marine organisms that are the food of many larger life forms. Other phosphates sink to the
bottom of bodies of water and blend with the sediment. Very slowly, over millions of years, this mixture forms rock, returning phosphorus to its original state.
Exercises: Biosphere: biogeochemical cycles
1. Name two processes by which carbon dioxide is captured and used to produce other substances.
2. How have human activities contributed to disrupting the carbon cycle?
3. Which biochemical cycle or cycles are involved in each of the following situations? a. sheep grazing in fields
b. the dead leaves left on the lawn last fall
c. the fire of a charcoal barbecue d. the steak you ate for supper yesterday
85
LIVING WORLD
86
CHAPTER 9
Studying Populations: A population is a group of individuals of the same species, living in a shared space at a specific point in time.
Population size refers to the number of individuals in a population.
o To calculate populations size:
Population density refers to the number of individuals per unit of area or volume.
o To calculate populations density:
Mark and recapture is method used to study animals; follow their migratory patterns; etc.
o To calculate populations size:
Population Distribution:
Population distribution is the way in which individuals are dispersed within their habitat.
Clumped Distribution Uniform Distribution Random Distribution
Individuals form groups to provide some protection predators & to feed
themselves more efficiently. It is the most common distribution.
Individuals are dispersed equally throughout the population’s habitat
due to competition for natural resources
Individuals are randomly & unpredictably dispersed across the
population’s habitat. It is the most rare distribution
Ecological factors:
An ecological factor is an aspect of a habitat that can affect the organisms living there Abiotic factors are ecological factors of physical or
chemical origin.
o Amount of light
o Soil or water pH o Terrain
o Depth of snow o Temperature
o Air humidity
Biotic factors are ecological factors related to the
actions of living organisms.
o Birth rate
o Disease o Amount of food
o Predation o Competition
o Human activity
Population size = (Average number of individuals per section x Total study area) Area of a section
Population density = ____Number of individuals_____
Space (area or volume) occupied
Population size = (# of marked animals x Total # of animals captured the 2nd time)
# of marked animals recaptured
87
Biological Cycles of a Population:
The biological cycle of a population is composed of alternating periods of rise and fall in its size. These periods are of fixed duration and are repeated
continually. As the population of prey increases – the population of predators
increases
As the population of prey decreases – the population of predators
decreases
The cycle repeats with the predators always following the cycle of the prey
Biodiversity: Biodiversity describes the variety of species living in a community. To determine the biodiversity of a community two
factors must be taken into consideration: species richness and relative abundance.
Species richness is the different number of species
in the community
Relative abundance is the number of individuals of
a particular species in relation to the total number of individuals in the community
Interaction between Individuals in a Community:
Competition is the interaction between living organisms that seek access to the same
resource in their habitat.
Predation is the interaction between two living organisms in which one feeds on the other. Parasitism is a type of
predation where a parasite feeds off a host.
Mutualism is the interaction between two living
organisms that benefits both organisms.
Commensalism is the interaction between two living
organisms in which one organism benefits from the relationship, while the other remains unaffected.
Exercises:
Population Size: 1. Does each of the following examples refer to a population or to the size of a population?
a. hares in Gaspésie
b. a private lake stocked with 240 trout
Predation
Parasitism
Low Richness High Richness
Less abundant
(uneven distribution) More abundant
(even distribution)
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c. snow geese migrating north
d. 628 000 caribou counted in northern Québec e. the frogs in a pond
f. cattails along a lakeshore
2. Based on the data below, describe the changes to the population size in a snow goose colony that has migrated
north. Data
Initial number of geese: 150 Number of births: 70
Number of deaths: – attributed to predators: 5
– attributed to hunting: 3
– attributed to exhaustion from the migration: 2 Number of geese that immigrated: 3
Number of geese that emigrated: 0
3. On the Île d’Anticosti, there are 21 white-tailed deer per square kilometre. The area of the island is 7943 km2.
Calculate the size of the white-tailed deer population living on the island.
4. Biologists are conducting a study of a duck population in a lake. In their first capture, 38 ducks were counted and marked with rings. In the second capture, 90 ducks were counted, of which 20 had rings. Calculate the size of
the duck population.
Populations: density and biological cycles
1. A population of 55 snowshoe hares lives on an island with an area of 55 000 m2. What is the population density of hares on this island?
2. Name the pattern of population distribution in each of the following examples. a. schools of herring along the coast
b. razorbill colonies on Île aux Grues
c. roaming packs of wolves d. snow geese flying in a “V” formation
e. pods of belugas in the St. Lawrence River (Fleuve Saint-Laurent) f. clover growing in a field
3. Is each of the following a biotic or an abiotic factor? a. Preadation
b. Temperature c. Air humidity
d. Competition
e. Soil pH
f. Birthrate g. Disease
h. Terrain
4. What are the limiting factors in the following situation? Soapy discharge causes blue-green algae to grow and
spread in a lake. The trout in the lake gradually die off.
Studying communities: biodiversity 1. What is the number of species in a community called?
2. The table below lists the contents of two aquariums, A and B, both with a capacity of 50 L. Answer the following
questions.
Aquarium A Aquarium B
5 goldfish 8 goldfish
3 striped fish 2 striped fish 2 snails 0 snails
0 bottom feeder 2 bottom feeders
4 green algae 2 green algae 1 fern 2 ferns
a. Compare the species richness of the two aquariums.
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b. Find the relative abundance of each of the species in the two aquariums.
Aquarium A Aquarium B
5 goldfish 8 goldfish 3 striped fish 2 striped fish
2 snails 0 snails 0 bottom feeder 2 bottom feeders
4 green algae 2 green algae
1 fern 2 ferns
c. Which aquarium has the greater biodiversity?
3. Identify the type of interaction between the living organisms in each of the following situations.
a. In winter, moose and deer look for the same food.
b. A hummingbird builds its nest in a tree. c. A louse feeds on a dog’s blood.
d. People do volunteer work. e. Certain fungi provide algae with the moisture they need to survive, and the algae provide food for the
fungi by photosynthesis. f. A person feeds his or her watchdog.
g. A hermit crab lives with a sea anemone in an empty seashell.
h. Crows eat the remains of a carcass left by a wolf. i. A carnivorous plant feeds on small insects.
j. Athletes run a 1500-m race at the Olympic Games.
Chapter 10
Ecosystem: An ecosystem is a community of living organisms
interacting with one another and with the nonliving
components of the environment they inhabit. Trophic Relationships:
Trophic relationships are the feeding connections among the living organisms in an ecosystem. The material and
energy flow is the exchange of matter and energy between the living organisms in an ecosystem and
between those organisms and their environment.
Producers Consumers Decomposers
Producers are autotrophic
organisms with the ability to
create organic matter from
inorganic matter in an ecosystem.
Producers can photosynthesize
to produce their own food. Producers are always at the
start of a food chain.
Consumers are heterotrophic organisms that
feed on other living organisms.
First order consumers are herbivores (they
consume plants).
Second order and up are either carnivores
(consume other consumers) or omnivores (consume other consumers & plants).
Note: Order is determined by how many steps the
consumer is from the producer.
Decomposers are
organisms that feed on
the waste (detritus) and
remains of other living organisms.
Decomposers can also
be referred to as detrivores.
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Chemical recycling is a natural phenomenon by which
decomposers make inorganic matter available in an ecosystem
by breaking down organic matter.
The material and energy (heat) flow is the exchange of matter
& energy between the living organisms in an ecosystem &
between those organisms and their environment.
Primary Productivity:
The primary productivity of an ecosystem is the amount of new biomass (total mass of organic matter in an ecosystem at any given time) generated by its producers.
Factors influencing primary productivity in an ecosystem:
o The amount of light
o The amount of water available o Access to essential nutrients for producers ( carbon, nitrogen, phosphorus, potassium)
o The temperature Disturbances:
A disturbance is an event that damages an ecosystem. It can lead to the elimination of organisms and alter the availability
of resources. Natural disturbances are triggered by environmental phenomena that can damage ecosystems
Examples: hurricane, ice storm, forest fire (of natural origin), etc.
Human disturbances are activities by humans that have damaging effects on ecosystems
Examples: logging, oil spills, mining, etc.
Ecological succession is the series of changes that occur in an ecosystem after a disturbance and that continue until the balance of the ecosystem is restored.
EST – Ecological Footprints:
Ecological footprints are estimates of the surface area individual humans or populations require to obtain the resources for
satisfying all their needs and to ensure the disposal of their waste.
Ecological footprint of a
population
= Land and water occupied by the
population
+ Land and water used to
produce goods and
services for the population
+ Land and water used
to dispose of the
population’s waste
EST – Ecotoxicology:
Ecotoxicology is the study of the ecological consequences of polluting the environment with various substances and radiation, released by human activity.
Factors influencing the toxicity of a contaminant:
o Concentration (the more concentrated a contaminant, the higher the risk that it is toxic)
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o Type of organism it comes in contact with (certain contaminants are toxic to some organisms but not to
others) o Length of exposure (the longer a contaminant is contact with an organism, the greater the toxicity)
A contaminant is any type of substance or radiation that is likely to cause harm to one or more ecosystems. Main
classes of contaminants:
o Inorganic contaminants (lead, arsenic, mercury, nitrogen oxides, phosphorus, etc.) o Organic contaminants (Insecticides, pesticides, polychlorinated biphenyls (PCBs), benzene, etc.)
o Microbiological contaminants (viruses and harmful bacteria) o Radioactive contaminants (Uranium, plutonium, radon, etc.)
The toxicity threshold is the level of concentration above which a contaminant causes one or more harmful effects
in an organism.
o Calculating toxicity threshold:
EST – Bioaccumulation and Bioconcentration: Bioaccumulation is the tendency among certain contaminants to accumulate over time in the tissues of living organisms.
The longer the organism lives the more contaminants it has accumulated
Bioconcentration (or bioamplification) is a phenomenon by which the concentration of a contaminant in the tissues of living organisms tends to increase with each trophic level.
The higher up the food chain the more likely an organism increases the concentration of contaminants in their
system
EST – Biotechnology: Biotechnology is the solution to counteract certain environmental problems
Biodegradation is the breaking down of organic matter into inorganic matter by microorganisms.
Bioremediation is a biotechnology for cleaning up a polluted site, using microorganisms that decompose the
contaminants.
Phytoremediation is a biotechnology that uses plants or algae to eliminate contaminants from a site.
Wastewater is water that is discharged after household or industrial use and that is polluted as a result of human
activities.
Exercises: Ecosystems and trophic relationships:
1. Name the trophic level of each of the living organisms below. a. Wolves
b. Frogs
c. Insects
d. Earthworms
e. Maple trees
f. Certain bacteria
g. Coyotes
h. Algae
i. Bears
Bioconcentration
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2. Draw a diagram of a food chain, using arrows and the organisms in the box below. Specify the trophic level of
each living organism in the chain.
plants, wolf, fungi, insects, rabbit, bacteria, fox
Ecosystem dynamics and disturbances:
1. Would each of the following situations have a positive effect or a negative effect on primary productivity?
a. warm temperatures in northern Québec b. sufficient supplies of nitrogen, carbon or phosphorus
c. a pond that dries up d. insufficient light
e. sufficient sunlight for photosynthesis
2. Compare Japan’s ecological footprint with the global footprint. What strikes you about the two figures?
Contamination: 1. To which class of contaminants does each of the following substances belong?
a. Arsenic b. Radon
c. Harmful bacteria
d. Benzene e. Polychlorinated biphenyls (PCBs)
f. Phosphorus
2. Mercury has been discharged from a factory. Place the following stages of bioaccumulation in chronological order. a. Minnows feed on zooplankton.
b. A factory spills mercury into a river.
c. Trout eat minnows. d. Zooplankton feed on phytoplankton.
e. Kingfishers eat trout. f. Phytoplankton feed in contaminated water.
3. Draw a series of asterisks to represent bioaccumulation in the following food chain.
Phytoplankton zooplankton small large belugas killer whales
fish fish
EST – Chapter 11
Factors for Character Traits among Organisms:
A character trait is a physical, psychological or physiological
attribute that may vary from one individual to another within the same species.
Chromatin is a mass of DNA and proteins within the
nucleus of most cells not undergoing division.
A chromosome is a structure that is formed when
chromatin contracts. It is visible under the microscope.
A karyotype is an ordered representation of an
individual’s chromosomes, obtained by grouping
them into pairs according to size.
A gene is a DNA segment that contains information
for making proteins.
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o DNA is composed of nitrogenous bases, sugar and phosphate
o The nitrogenous bases are always found in specific pairings – Adenine with Thymine and Cytosine with Guanine
DNA vs RNA
DNA RNA
DNA is double-stranded
Thymine is present
The sugar is deoxyribose
RNA is single stranded
Uracil replaces thymine
The sugar is ribose
Different types of RNA include:
o Messenger RNA (acts as a messenger for carrying instructions about the gene to the ribosome) o Transfer RNA (Transfers the amino acids in the cell’s cytoplasm to the ribosomes)
A protein is a molecule that plays a specific role in the functioning of an organism and in the expression of its
character traits.
Examples: o Support (elastin is a protein that makes the skin firm yet elastic)
o Transport of substances (hemoglobin is a protein that carries oxygen in the blood)
o Control and message relay (hormones are proteins that control cell functions and relay messages in the body – insulin helps control the amount of sugar in the blood)
o Immunity (antibodies are proteins that protect us from disease) o Catalysis (enzymes are proteins that speed up biochemical reactions in the body – amylase breaks down
starch to speed up digestion)
Protein synthesis is the creation of proteins by cells.
o Transcription of DNA into messenger RNA – The double helix of the DNA id unzipped, and a messenger RNA molecule is built by copying the DNA nucleotide sequence, following the rules of base
pairing (U-A, C-G). The genetic information of the DNA is thus copied to the messenger RNA.
o Attachment of the messenger RNA to the ribosome – After the messenger RNA leaves the nucleus, it attaches itself to a ribosome. The ribosome slides over the messenger RNA and reads the nucleotides
by groups of three, or triplets. When it comes across an AUG triplet, the protein building begins.
o Translation of the messenger RNA into a protein – The ribosomes reads the nucleotide triplets one after another. Each triplet determines the amino acid that must be added to the chain according to a
code called the genetic code. The amino acids are brought up to the chain by transfer RNA molecules, which carry the nucleotide triplet complementary to that of the messenger RNA on one side and the
appropriate amino acid on the other. The amino acids then link together, and the RNA is released.
o End of protein synthesis – When the ribosome encounters a UAA, UAG or UGA nucleotide triplet, the amino acid chain is complete. The protein is then released from the ribosome, folds into its functional
shape and performs its role in the body.
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Principals of Heredity:
Humans have 22 pairs of autosomes and one pair of sex chromosomes
o Autosome – any of the pairs of chromosomes in humans, which aren’t sex chromosomes o Females have two X chromosomes
o Males have an X chromosome and a Y chromosome o The genes on the X chromosome are different from the genes on the Y chromosome
A gene is a sequence of DNA that is expressed as a physical trait
o Example: One gene controls tongue-rolling ability and another gene controls the presence of cheek
dimples. o A genotype is the particular combination of alleles that an individual has received from its parents.
Example: The possible genotypes for alleles A and a are AA, Aa and aa o The phenotype is the physical manifestation of a trait, including a combination of genetic and
environmental factors
Genes on the X chromosome are sex-linked
o Sex-linked traits occur more frequently in human males than in females, since they have only one X chromosome
o Normal females may act as carriers for recessive sex-linked traits
Examples: colourblindness, hemophilia
Nondisjunction occurs when the membranes of a pair of homologous chromosomes do not separate during
meiosis. o This results in extra or missing
chromosomes in the offspring
o Down’s syndrome (also known as triosomy 21 syndrome) is a
chromosomal disorder caused by nondisjunction
3 copies of chromosome
21 in the cells of people with this disorder
o Amniocentesis is used to diagnose Down’s syndrome and other
heredity disorders before the baby is born
The order of genes on a chromosome is
determined from the rate of crossing over
o Genes that are far apart from each other cross over more often
than genes that are close to each
other o Studying linkage and crossing over is to help determine the order of the genes
Mutations are sudden changes in genes of chromosomes
o Mutations carried in gametes are transmitted to the next generation
o Radiation and certain chemicals cause mutations o Harmful mutations hinder an organism’s survival
Albinism in plants is lethal – they die – no chlorophyll, no food production o Helpful ones cause variations that may aid an organism’s survival
o Breeders make use of mutations in their work
o Polyploid cells have more than 2 sets of chromosomes and represent a kind of mutation Scientists use a chemical called colchicines to cells during mitosis (ex: farmers\breeders apply it
to seeds to have larger fruit, etc)
Alleles are alternative versions of a gene for a trait and are located at the same locus in homologous
chromosomes
o A gene is made up of a minimum of two alleles, but often more, and always in multiples of two. Alleles
are always paired – an equal number come from the male and female.
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o Dominant and recessive alleles are indicated with upper and lower case letters (ex: A and a), and
codominant alleles are indicated with subscripts 1 and 2 (ex: C1 and C2) A dominant allele is the more influential allele in a genetic pairing. The presence of a dominant
allele always results in the manifestation of the dominant trait A recessive allele is the less influential allele in a genetic pairing. Recessive traits only manifest if
no dominant gene is present
Codominance occurs when both of the paired alleles exert influence on a trait. When two different codominant alleles form a pairing, the phenotype is a mixture of the two different types
(ex: The offspring of a red flower and a white flower might be pink if the colour alleles are codominant.)
Homozygous describes a genotype that has paired alleles
that are identical (ex: AA or aa)
Heterozygous describes a genotype that has paired alleles
that are not identical (ex: Aa) Polygenic describes a trait
controlled by many genes. For
example, a person’s height is the result of the cumulative
effects of many genes, each with a small influence on
growth. Traits controlled by a single gene produce discrete
phenotypes (small, present or
absent), while polygenic traits produce a range of phenotypes.
Multiple gene inheritance is responsible for the
gradation of expression for many traits seen in a
population o 2 or more pairs of genes control a single
trait o Each gene pair works according to the
laws of dominance and segregation
A pure line is a group of individuals of the same
species, which, for a specific character trait, produces only offspring with the same trait,
without variation (ex: flowers, dogs)
Crossbreeding is the exchange of gametes between two different individuals during sexual reproduction
o A hybrid is an individual obtained by the crossbreeding of two genetically different individuals Punnett squares are used to statistically predict the outcomes of crossbreeding two genetically
different individuals
o A generation is a group of individuals descended from common parents
Cloning: Cloning is the reproduction of an individual, part of that individual or one of its genes in order to obtain an exact
copy.
Natural cloning produces genetically identical individuals through asexual reproduction
Artificial cloning:
o Artificial plant cloning is usually used in the agricultural industry
o Animal cloning is used usually with livestock (ex: meat or wool) o Human cloning:
Reproductive cloning is the application of cloning techniques to obtain a new individual
genetically identical to the one being cloned Therapeutic cloning is the application of cloning techniques to obtain tissues or organs genetically
identical to those of a person in need of a transplant or medical grafting
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o Molecular cloning is the production of multiple copies of the same gene (also known as DNA or gene
cloning) Mainly used to research and study genetic disorders or diseases
Exercises:
1. For each genotype, indicate whether it is heterozygous (HE) or homozygous (HO)
AA ____
Bb ____ Cc ____
Dd ____
Ee ____
ff ____ GG ____
HH ____
Ii ____
Jj ____ kk ____
Ll ____
Mm ____
nn ____ OO ____
Pp ____
2. For each of the genotypes below, determine the phenotype.
Purple flowers are dominant to white flowers
PP ___________________________ Pp ___________________________
pp ___________________________
Brown eyes are dominant to blue eyes
BB ___________________________ Bb ___________________________
bb ___________________________
Round seeds are dominant to wrinkled RR ___________________________
Rr ___________________________ rr ___________________________
Bobtails are recessive (long tails dominant) TT ___________________________
Tt ___________________________ tt ___________________________
3. For each phenotype, list the genotypes. (Remember to use the letter of the dominant trait)
Straight hair is dominant to curly. ____________ straight
____________ straight ____________ curly
Pointed heads are dominant to round heads. ____________ pointed
____________ pointed ____________ round
4. Set up the square for each of the crosses listed below. The trait being studied is round seeds (dominant) and
wrinkled seeds (recessive)
Rr x rr
What percentage of the offspring will be round? ___________
Rr x Rr
What percentage of the offspring will
be round? ___________
RR x Rr
What percentage of the offspring will be round? ___________
5. A TT (tall) plant is crossed with a tt (short plant). What percentage of the offspring will be tall? ___________
6. A Tt plant is crossed with a Tt plant. What percentage of the offspring will be short? ______
7. A heterozygous round seeded plant (Rr) is crossed with a homozygous round seeded plant (RR). What
percentage of the offspring will be homozygous (RR)? ____________
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8. A homozygous round seeded plant is crossed with a homozygous wrinkled seeded plant. What are the genotypes
of the parents? __________ x __________
What percentage of the offspring will also be homozygous? ______________
9. In pea plants purple flowers are dominant to white flowers. If two white flowered plants are cross, what percentage of their offspring will be white flowered? ______________
10. A white flowered plant is crossed with a plant that is heterozygous for the trait. What percentage of the offspring
will have purple flowers? _____________
11. Two plants, both heterozygous for the gene that controls flower color are crossed. What percentage of their
offspring will have purple flowers? ______________
What percentage will have white flowers? __________
12. In guinea pigs, the allele for short hair is dominant. What genotype would a heterozygous short haired guinea pig have? _______
What genotype would a purebreeding short haired guinea pig have? _______
What genotype would a long haired guinea pig have? ________
13. Show the cross for a pure breeding short haired guinea pig
and a long haired guinea pig. What percentage of the offspring will have short hair? __________
14. Show the cross for two heterozygous guinea pigs.
What percentage of the offspring will have short hair? ________
What percentage of the offspring will have long hair? _______
15. Two short haired guinea pigs are mated several times. Out of 100 offspring, 25 of them have long hair. What are the probable
genotypes of the parents? ________ x ___________ Show the cross to prove it!
Genetic Crosses that Involve 2 Traits In rabbits, grey hair is dominant to white hair. Also in rabbits, black eyes are dominant to red
eyes. These letters represent the genotypes of the rabbits:
GG = gray hair Gg = gray hair
gg = white hair
BB = black eyes Bb = black eyes
bb = red eyes
1. What are the phenotypes (descriptions) of rabbits that have the following genotypes:
Ggbb ____________________ ggBB ________________________
ggbb ____________________ GgBb _________________________
2. A male rabbit with the genotype GGbb is crossed with a female rabbit with the genotype ggBb The square is set up below. Fill it out and determine the phenotypes and proportions in the offspring.
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How many out of 16 have grey fur and black eyes? ________
How many out of 16 have grey fur and red eyes? ________
How many out of 16 have white fur and black eyes? ________
How many out of 16 have white fur and red eyes? ________
3. A male rabbit with the genotype GgBb is crossed with a female rabbit with the genotype GgBb The square is set
up below. Fill it out and determine the phenotypes and proportions in the offspring.
How many out of 16 have grey fur and black eyes? ________
How many out of 16 have grey fur and red eyes? ________
How many out of 16 have white fur and black eyes? ________
How many out of 16 have white fur and red eyes? ________
4. Show the cross between a ggBb and a GGBb. You'll have to set the square up yourself!
Codominance and Incomplete Dominance 1. Practice setting up keys for the phenotypes listed in each set. Remember that the "medium" trait must always be
heterozygous. a. Birds can be blue, white, or white with blue-tipped feathers.
b. Flowers can be white, pink, or red.
c. A Hoo can have curly hair, spiked hair, or a mix of both curly and spiked. d. A Sneech can be tall, medium, or short.
e. A Bleexo can be spotted, black, or white. f. Now, can you figure out in the above list, which of the letters represent codominant traits and which are
incomplete.
Codominant _____________ Incompletely Dominant ________________
2. In Smileys, eye shape can be starred, circular, or a circle with a star. Write the genotypes for the pictured
phenotypes
3. Show the cross between a star-eyed and a circle eyed.
a. What are the phenotypes of the offspring? ____________ b. What are the genotypes? __________
4. Show the cross between a circle-star eyed, and a circle eyed. a. How many of the offspring are circle-eyed? ___________
b. How many of the offspring are circle-star eyed? ____________
5. Show the cross between two circle-star eyed.
a. How many of the offspring are circle-eyed? ___________ b. How many of the offspring are circle-star eyed? ____________
c. How many are star eyed? ____________
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X-linked Genes
*In fruit flies, eye colour is a sex linked trait. Red is dominant to white. 1. What are the sexes and eye colours of flies with the following genotypes:
XRXr ____________ XRY ____________ XrXr ___________
XRXR ____________ XrY ____________
2. What are the genotypes of these flies:
White eyed, male ____________ Red eyed male ___________ White eyed, female ____________ Red eyed, female
(heterozygous)
___________
3. Show the cross of a white eyed female XrXr with a red-eyed male XRY.
4. Show a cross between a pure red eyed female and a white eyed male. What are the genotypes of the parents:
_________________ & _________________ How many are:
White eyed, male ______ White eyed, female ______
Red eyed, male ______
Red eyed, female ______
5. Show the cross of a red eyed female (heterozygous) and a red eyed male. What are the genotypes of the parents: __________________ & _________________
How many are:
White eyed, male ______ White eyed, female ______
Red eyed, male ______
Red eyed, female ______
What if in the above cross, 100 males were produced and 200 females. How many total red-eyed flies would
there be? ______
6. In humans, hemophilia is a sex linked trait. Females can be normal, carriers, or have the disease. Males will
either have the disease or not (but they won’t ever be carriers).
XHXH Female, normal XHY Male, normal XHXh Female, carrier XhY Male, hemophiliac
XhXh Female, hemophiliac
Show the cross of a man who has hemophilia with a woman who is a carrier. What is the probability that their children will have the disease? ______
7. A woman who is a carrier marries a normal man. Show the cross. What is the probability that their children will
have hemophilia? What sex will a child in the family with hemophilia be?
8. A woman who has hemophilia marries a normal man. How many of their children will have hemophilia, and what
is their sex?
9. In cats, the gene for calico (multicoloured) cats is codominant. Females that receive a B and an R gene have black and orange splotches on white coats. Males can only be black or orange, but never calico. Here’s what a
calico female’s genotype would like: XBXR. Show the cross of a female calico cat with a black male?
What percentage of the kittens will be black and male? What percentage of the kittens will be calico and male?
What percentage of the kittens will be calico and female?
10. Show the cross of a female black cat, with a male orange cat. What percentage of the kittens will be calico and female?
What colour will all the male cats be?
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