UEQHow is an understanding of chemistry

critical in our lives?

LEQHow are the different branches

of chemistry related?

Chemistry: The study of the matter and the energy involved the change of matter.

1. Organic Chemistry: study of carbon containing compounds (C-H or O or N or S) in which carbon is written first.

2. Inorganic chemistry: the study of matter that is not organic.

a. Physical chemistry: explains the behavior and change in matter related to the change in energy.

b. Analytical chemistry: components and composition of matter.

3. Biochemistry: the study of chemistry of living systems.

Quantitative Analysis (Data): focus on the amount of a substance present.23% Na by mass or 54 ml or 23g MgO

Qualitative Analysis (Data): focus on the detection or identification of a substancerhombic crystal, viscous fluid, changes to a blue color when reacting, precipitate, or oxidation.

1. The MiO turned the water red.2. The substance is massed to 0.05 g3. The liquids turned to a solid when mixed.4. The red cloth is softer.5. Mass 5 g of NaCl6. The mixture felt warm when mixed.7. Magnesium burns at 2300oF8. 1.25 moles of PbCl2 solid is formed.

9. The coach placed the bag on runners leg and it felt cool.

LEQ: How is matter and energy linked?

Matter: any substance that has mass and occupies space.?What is not matter?

heat, light, electromagnetic fields

Substance: Of a uniform and defined composition.

Weight: influence of gravity on matter.

Mass: quantity of matter present, NOT defined by gravity.

Two types of Energy:1. Kinetic energy: energy of motion. All matter is in

constant state of motion.KE = ½ mv2

m = mass and v = velocity (how fast)

The theoretical temperature where all matter stops (even electrons around the nucleus ) is called: absolute zero.

2. Potential energy: energy of position or stored energy.

PE = mgh (gravitational potential) m = mass ; g = acceleration due to gravity ( 9.8 m/s2) ; h = height

Based on: KE + PE = Mechanical energy

1. Law of the Conservation of Matter and Energy: there is NO detectable increase or decrease in mass or energy when a change occurs. Total energy/mass is constant.

2. Scientific Law: Observation for which there is no exception. The relationship is supported by many experiments. Gravity

a. Theory: plausible explanation of an observation.

1. Solid: define shape and volumeamorphous solid: not uniform shape

like bricks and window glass.crystilline solid: uniform pattern and

structure like a diamond or salt.

2. Liquid: defined volume with NO defined shape.

3. Gas: NO defined shape or volume. (Plasma is a high energy gas).

Chemical Property: that which is defined by the chemical composition of matter

Chemical change: light, heat, gases, odor, and a change in the color

Physical Property: the structural make-up of matter.

Physical changes: change of color, luster, malleablity, ductility, evaporation, condense, sublimation.

Extensive: focus on the amount of matter present.

mass, volume, temperatureIntensive: independent on the amount of

material.freezing point, boiling point, density

ALL chemical properties are intensive

1. The mixture produced bubbles (a gas)2. When mixture a solid precipitation formed3. Lead is more dense than iron.4. The atomic mass of carbon is 12.01 amu5. All gases occupy 22.4 L @ STP6. Pure water boils @ 100oC @ STP7. The mixture felt warm after mixing.8. The solution changed from clear to red.

LEQ: What is the link between science

theory and law?

A systematic approach to solve a problem or explain an observation.1. Make an observation: thru the senses

a. Inference: observed opinionb. qualitative data: describes physical characteristics of matter like color,

odor, shape.c. quantitative data: uses numerical

notation to describe matter like 50 ml, 250 g or 5 m.

2. Hypothesis: from the observations, a tentative reasoning or plausible outcome (If Then)

3. Experimentation: set of controlled observation to test the hypothesis.a. Independent variable: variable that changes during the experiment but is NOT changed as a result of the experiment (plotted on the x-axis). The ‘If’b. Dependent variable: variable that changes in response to the experiment (plotted on the y-axis). The ‘Then’.

c. Control variables: many, many other factors that might effect outcome but are made to stay constant

How does a ‘Control Group’ differ from ‘Controlled Variables’Control Group Control Variables

Only one Many, many at same timeUsed to compare Used to determine against a population if the dependent

variable is the cause for the

outcome.

4. Collect data: expressed in charts, graphs, or tables. Large amount of data in a small package.

5. Conclusion: based on data your hypothesis is accepted or rejected. (NEVER wrong)

(results in a theory or a law)Experimentation is used in applied research

and/or as pure research

Theory is a plausible explanation for an event based on observations.

Shown in a model to show either by mathematics or structure the explanation.

Law is a regular occurring event supported by many experiments and mathematics

LEQ: How do graphs help to

summarize data?

Line Graph: shows trends (Best-fit-line)

Bar graph: shows how quantities vary with factors.

Pie or Circle graph: Show how factors are divided up or distributed

Points of Interest:1. We use coordinates in all 4 quadrates.2. X-axis is the independent variable. It is

independent of the affects of the experiment (deliberately manipulated, unaffected)

3. Y-axis is the dependent variable (changes in response to manipulation)

4. Axis must always be evenly distributed5. Must use labels with units

6. Title the graph7. Slope = rise/run or ( m =Δy/Δx )8. Linear direct defined by k = y/x9. Inverse (hyperbola) defined by k = xy10. Direct to the square (parabola) defined by

k = y/x2

11. To ‘interpolate’ is to predict relationships between data points

12. To ‘extrapolate’ is to predict relationships outside of the data points

13. ‘Direct’ relationship defines constant motion. Unchanging.

14. ‘Inverse’ or ‘direct to the square’ relationship defines variable motion. Changing over time.

15. Slope defines how fast or slow (intense or passive). NOT direction.

16. Draw a ‘Line of Best Fit’. We DO NOT connect the dots b/c of uncertainty.

1. Draw a line graph that would show a positive slope of 0.5 m/s.

2. Draw a graph that best represents 52% green, 24% red, 15% blue , 7% black and 2% unknown.

3. Draw a line graph that would indicate a rate of – 1.0 m/s

4. Draw a graph that would represent your grades depending on the period of the day.

Volume (L) Mass (g)

2.0 5.4

4.0 10.8

6.0 16.2

8.0 21.6

10.0 27.0

12.0 32.4

14.0 38.8

1. Which variable is placed on the x-axis? Why?2. Which variable is placed on the y axis? Why?3. Which variable is the independent variable?

Why?4. What type of relationship is shown in the

graph?5. What type of line is drawn?6. What is the mass at 9L?7. What is the volume at 86.4 g?

LEQ: What is the meaning behind a unit?

SI Units Measurement Unit System Length meter m Mass kilogram kg Time second s Temperature Kelvin K Volume Liter L Volume Cubic meter m3

Commonly Used Metric PrefixesPrefixes Symbol BaseMega- M 10 6

kilo- k 10 3

centi- c 10 -2

milli- m 10 -3

micro- μ 10 -6

nano- n 10 -9

pico- p 10 -12

Meaning of the prefix defines the conversion:Mega- means 1 000 000x larger than 1kilo- means 1000x larger than 1

There are 1000 g in 1 kgcenti- means 100x smaller than 1

There are 100 cg in 1 gmilli- means 1000x smaller than 1

There are 1000 ml in 1 m Lmicro- means 1 000 000x smaller than 1

Commonly Used Conversion Factors:1 m = 3.28 ft 1 mile = 5280 ft 1 in = 2.54 cm

3600 s = 1 hr 1 kg = 2.2 lbs 1 m3 = 1003 cm3

**Metric conversions are defined by the prefix**1000 m = 1 km 1 s = 1 x 109 ns1 g = 100 cg 1 x 10 6 μm = 1 m

*Derived units: combination of units ( m/s or g/yr)*Two steps, converting LIKE units only

1. What is the symbol for means 1000x smaller than one: _______________

2. What does the prefix kilo- means: ________3. How many pounds in 1 kg _________4. One hour has how many seconds _________5. A recipe calls for 1 oz on sugar, how many

grams would this be _____________6. A gallon of milk is equal to how many

liters___________7. What is the prefix for 10-2 __________

8. What is the SI unit for time __________9. What is the SI unit for temperature _________10. What is the prefix for 103 _____________11. What is the SI unit of mass ___________12. What is the unit symbol for nano- _______13. How large is a nano- compared to one ____14. How many millimeters are in one meter _________15. How many grams are in one kilogram _________

LEQ: How does dimensional analysis help in understand relationships between

measurements?

Method used to convert units:1. Read the problem to get an idea of the problem. Focus on units!2. Read the problem a second time for specifics. Focus on units!3. Make a list of knows and unknown.4. Define standard relationships. (Conversion Units)5. Set-up the numerator and denominator in a manner in which units cancel. Start with the know & arrange units to solve for unknown.

If the undesired units do not cancel because of lack of an algebraic relationship, then your set-up is wrong!!!

Re-evaluate!!!!!

1. You are in Morocco. You ask a man how far it is to the market. He replies 4.5 Km east. How far is this in miles?

2. The police clock you driving ar 15.64 m/s in a 35 mile/hr zone. Do you get a ticket?

3. Your diet allows for 105 g of chocolate per day. A single chocolate bar contains 4.9 oz, how much of that candy bar are you allowed to eat?

1. If gasoline cost $1.32/gal, what does it cost in cents/L ?

2. A golf ball weights 4 ounces. How many golf balls makes up 2.5 tons ?

3. The density of water is 1.0 g/cm3. What is the equivalent density in lb/ft3 ?

4. How fast is 55 miles per hour (mi/hr) in meters per second (m/s) ?

5. How much would it cost to cover a 12 ft x 15 ft room with carpet at a cost $12.95 per square yard ?

What is different in the math used in chemistry?

!!!!!!!!!!!! UNITS !!!!!!!!!!!!!!

First number between 1 and 10 x base 10(-) exponent = decimal number

2.5 x 10-5 m = 0.000 025 m(+) exponent = whole number

2.5 x 103 m = 2500 m

When writing a numerical number into scientific notation:1. If the # gets smaller, the exponent gets larger.2. If the # gets larger, then the exponent will get smaller.3. Negative exponents means the # is less than 14. positive exponents mean the # is greater than 1.

When adding/subtracting in sci. notation make the exponents the same and then add/subtract the first # and carry the common exponent. (overhead)

When multiplying multiply the first # and add exponents

When dividing divide the first # and subtract the exponents.

ALWAYS express the final answer in proper notation.

Write into scientific notation:1. 0.00205

2.05 x 10-3

2. 780 0007.8 x 105

3. 0.000 0055 x 10-6

Write in numerical notation:1. 4.85 x 10-3

0.004852. 1.02 x 105

102 0003. 8.30 x 10-2

0.0830 (yes that last zero is significant)

Multiply add exponents(2.0 x 10-2)(6.0 x 105) =12 x 10(-2 + 5) = 12 x 103 = 1.2 x 104

(exponent has an inverse relationship to the first number)Divide subtract exponents

(1.2 x 1014)/(6.0 x 1023) = 0.2 x 10(14-23) = 0.2 x 10-9 = 2 x 10-10

Add and Subtract move the decimal to get a common exponent and then carry down that exponent.1. Increase in exponent, decrease in the number.2. Decrease in the exponent, increase in the number.3. MUST express in scientific notation

Calculator

1) 2.05 x 105 +3.75 x 106

2) 9.84 x 10-3

-1.25 x 10-2

1. 2.5 days = ______ sAns: 216000s

2. 35 km = _______ mmAns: 3.5 x 10 7 mm

3. 6.71 x 10 11 μg = _________kgAns: 671 kg

4. 2.4 m/s = __________ miles/hrAns: 5.37 miles/hr

Accuracy refers to how close a measured value is to an accepted value or standard. Depends on the instrument used.

Precision refers to how close a series of measurements are to one another. This is the repeatibilility of the measurement.

With decimal: draw an arrow from the left to right and the first non-zero and all other numbers are significant, even the zeros.

0.002050 850.02 0.002Without decimals: draw an arrow from right

to left and the first non-zero and all other numbers are significant, even the zeros.

2005 20 000 1020

Round off to the smallest digits in the problem:

How many Sig Figs:1) 0.0845 kg = _____ 2) 37.00 = _____3) 0.000 053 = _____ 4) 0.5003 = _____

Multiply and Divide: the answer has the same number of sig figs as the least number of sig figs expressed in the problem.25.02 x 1.9

47.538 = 482.25/0.120

18.75 = 18.8

Adding and Subtracting: The answer is to be expressed with the same number of sig figs to the right of the decimal as the least number of to the right of the decimal stated in the problem.

55.002 + 75.8 =130.802 = 130.8

450 – 5.003 =444.997 = 445

Part x 100 Whole

Experimental Error:Experimental - Theoretical x 100

Theoretical

Describes the amount of matter in a given volume.

D = mass/volumeThe density of water at 4oC = 1.0 g/ml

Units like kg/L or g/ml or g/cm3

Specific Gravity is the density of a substance compared to the density of water.

density of substance/density of water

Standard points for water at 1atm: Kelvin Celsius Fahrenheit Boiling 373K 100oC 212oF Freezing 273K 0oC 32oF Absolute 0 K -273oC -419oF

Zero

Convert oC from oF oC = 5/9 (oF – 32 )

Convert oF from oC oF = (9/5 x oC) + 32

Convert K from oC K = oC + 273

Convert oC from K oC = K – 273

1. 95oF = ________ oC oC = 5/9 (95-32)oC = 35oC

2. 53oC = _________ K K = 53 + 273 K = 326 K

3. 42oC = __________ oFoF = (9/5 x 42) + 32oF = 107.6 oF

4. 340 K = _________ oCoC = 340 – 273oC = 67 oC

5. 37oC = __________oF oF = (9/5 x 37) + 32oF = 98.6 oF

Heat is NOT temperature or HOT/COLD

Heat is energy

Specific Heat: ΔH = m x Cp x ΔT Cp = the amount of energy needed to change the temperature of 1 g of a substance 1 oC

LEQ: How is matter classified?

Mixture: combination of 2 or more pure substances:1. components of a mixture will vary2. properties of a mixture will vary3. components maintain own chstc.4. can be separated physically

Not uniform throughoutComponents can be distinguishable

pizzamilkoil based paintconcrete

Uniform composition throughoutComponents are indistinguishable

salt waterair (called a solution)brass (called an alloy)

Pure Substance: composed of a single substance or the different substances are combined in a uniform composition.1. fixed uniform composition2. Can NOT be separated physically.3. Can be changed through a chemical method. 4. properties will NOT vary

Compound: combination of 2 or more elements1. composition is in a defined ratio by mass (Law of Definite Proportions)

H2O v. H2O2

Element: simplest form of matter1. represented in elemental symbols2. found on the periodic table.