New 2011 y11 s1.5 CHEMISTRY WORKBOOK2
Transcript of New 2011 y11 s1.5 CHEMISTRY WORKBOOK2
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INDEX
INDEX......................................................................................................................................................3
Achievement Standard..........................................................................................................................12
USEFUL WEB PAGES......................................................................................................................16
EXAMINERS REPORT 2009............................................................................................................ 17
Current Organisation of the Elements in the Periodic Table................................................................ 24
ELEMENT NAMES AND SYMBOLS.................................................................................................25
THE STRUCTURE OF THE ATOM...................................................................................................... 26
ISOTOPES........................................................................................................................................ 28
Relative atomic mass (Ar).............................................................................................................29
This is the mass of an atom compared to the mass of the C isotope, which is arbitrarily given a
value of exactly 12.00. Because the Ar measures the average value of an element ( and takesinto account the relative amount of each isotope present in nature) the value may not always bea whole number e.g the Ar for Cl is 35.5 because it exists as both the Cl (75%) and the Cl(25%) isotopes. Even carbon which is used as the standard reference has an Ar value of 12.01because of the small amount of the C isotope present in all naturally occurring carbon samples.However, for the accuracy we require, in most cases we round off the Ar values to the nearestwhole numbers e.g. H =1, O = 16, C = 12..................................................................................... 29
ELECTRON CONFIGURATION 33
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METALS AND ACIDS........................................................................................................................62
PRACTICAL 2....................................................................................................................................63
Results...................................................................................................................................................64Fe................................................................................................................................................... 64
ACIDS AND BASES.............................................................................................................................66
Some organic acids that you should know are.............................................................................. 66
HOW ACIDS WORK..........................................................................................................................66
Practical 3.......................................................................................................................................... 67
PRACTICAL 4....................................................................................................................................69
Name of Acid..................................................................................................................................... 69
pH meter reading............................................................................................................................... 69
Strong or weak ..................................................................................................................................69
Acid or base?.....................................................................................................................................69
Ethanoic Acid.....................................................................................................................................69
Sulfuric Acid.......................................................................................................................................69
Hexanoic Acid....................................................................................................................................69
Hydrochloric acid............................................................................................................................... 69
Ammonia............................................................................................................................................69
Sodium bicarbonate 69
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What would you expect to observe at the point of neutralisation?....................................................... 82
COMMONLY USED INDICATORS.......................................................................................................83
QUESTIONS (use the table)................................................................................................................. 83What is the pH of a solution if............................................................................................................... 83
UI = Yellow-green ...........................................................................................................................83
Bromothymol Blue = blue ...............................................................................................................83
Is it possible to use methyl orange to indicate a neutral solution? Explain your answer.....................83
__________________ ................................................................................................................83
__________________ ................................................................................................................83
__________________ ................................................................................................................83
Solution X turns blue with litmus and solution Y turns blue with bromothymol blue. Which solution, Xor Y is more basic? . .............................................................................................................................83
What is the pH value of the following solutions.................................................................................... 83
Acid rain turns yellow in bromothymol blue and purple with geranium red..........................................83
pH = ...............................................................................................................................................83
Sea water turns pink with phenolphthalein, and green with bromothymol blue....................................83
pH = ...............................................................................................................................................83
Battery acid turns red with methyl orange and orange with bromothymol blue....................................83
pH 83
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the amount of hydrochloric acid used up per minute or.................................................................... 85
the amount of magnesium chloride produced per minute or.............................................................85
the amount of hydrogen produced per minute.................................................................................. 85In this reaction it is easiest to measure the amount of hydrogen produced per minute. Thehydrogen is collected as it bubbles off and its volume is measured. A suitable apparatus is shownbelow..................................................................................................................................................85
When the flask is tipped up the two reactants mix. The gas produced pushes its way into thesyringe and the plunger moves out. The following results were obtained my measuring the volumeevery half-minute............................................................................................................................... 85
Time/minutes..................................................................................................................................... 86
0......................................................................................................................................................... 86
0.5...................................................................................................................................................... 86
1.0...................................................................................................................................................... 86
1.5...................................................................................................................................................... 86
2......................................................................................................................................................... 86
2.5...................................................................................................................................................... 86
3.0...................................................................................................................................................... 86
3.5...................................................................................................................................................... 86
4.0...................................................................................................................................................... 86
4 5 86
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Plot these results on a graph with volume of hydrogen on the vertical axis (y-axis), and time on thehorizontal axis (x-axis).......................................................................................................................86
Answer the following questions from the graph................................................................................ 87
From the graph above, how can you tell when the reaction is over?................................................87
________________________________________________________________________________________________________________________________________________________________................................................................................................................................................... 87
From the graph answer the following questions................................................................................87
How much hydrogen is produced in .................................................................................................87(i) 2.5 minutes? ____________________...................................................................................... 87
(ii) 4.5 minutes? ___________________.........................................................................................87
How many minutes does it take to produce .....................................................................................87
(iii) 10 mL of hydrogen? _______________..................................................................................... 87
(iv) 20 mL of hydrogen? ______________....................................................................................... 87
(v) What is the rate of reaction in the fourth minute? _________...................................................87
Note that in carrying out a reaction of a metal with an acid, the metal must first of all be rubbed withsandpaper to remove the metal oxide coating from the surface. If this is not removed it will slowdown the initial rate of reaction..........................................................................................................87
Collision Theory................................................................................................................................. 87
Finally, it is a fact that the more frequently effective collisions occur, the faster the rate of reaction.Th f f t th t ff t th t f ti b ff ti th f ( d ibl th
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Note these things about the graph:................................................................................................... 89
Curve A is steeper than curve B which tells you that the reaction was faster in A than in B............89
In A, reaction lasts 60 seconds, in B it lasts for 120 seconds........................................................... 89The rate of reaction in A is double the rate in B i.e. the rate of reaction has doubled when theconcentration of acid was doubled.................................................................................................... 89
Both reactions produced 60 mL of hydrogen. The volume of gas is the same because bothexperiments used the same amount of magnesium, and excess acid............................................. 89
Practical 11: How concentration affects rate of reaction...................................................................89
2. Surface area..............................................................................................................................91
If a solid is chopped, crushed or ground into smaller pieces, the surface area of the sample isincreased and more particles are exposed at the surface to react. Thus powdered marble has amuch greater surface area than marble chips. When the surface area is increased the rate ofreaction is also increased since there are more particles exposed for collision with anotherreactant. Again it is the frequency of collisions that increases leading to a faster rate of reaction.The total number of collisions does not increase assuming the other reactant is in excess............91
3. Temperature..............................................................................................................................92
When temperature is increased the particles gain kinetic energy and this has two effects. Firstlythey move faster and therefore collide with other particles more often. Secondly since the particleshave more energy, it is more likely that the collisions will have enough energy to result in a reaction(ie a larger proportion of the collisions will exceed the activation energy so that reaction occurs).Thus increasing the temperature results in both an increase in the frequency of collisions and in theeffectiveness of the collisions. This leads to an increase in reaction rate .......................................92
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6......................................................................................................................................................... 92
1......................................................................................................................................................... 92
1......................................................................................................................................................... 923......................................................................................................................................................... 92
4......................................................................................................................................................... 92
3......................................................................................................................................................... 92
4......................................................................................................................................................... 92
25....................................................................................................................................................... 92
25....................................................................................................................................................... 92
35....................................................................................................................................................... 92
50....................................................................................................................................................... 92
35....................................................................................................................................................... 92
50....................................................................................................................................................... 92
Foil..................................................................................................................................................... 92
Powder...............................................................................................................................................92
Foil..................................................................................................................................................... 92
Powder...............................................................................................................................................92
Powder...............................................................................................................................................92
F il 92
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Strong acid, weak acid, strong base, weak base or neutral Substance.........................................100
pH.................................................................................................................................................... 100
Category.......................................................................................................................................... 100Lemon Juice.................................................................................................................................... 100
5....................................................................................................................................................... 100
Hydrochloric Acid.............................................................................................................................100
1....................................................................................................................................................... 100
Sodium Hydroxide........................................................................................................................... 100
14..................................................................................................................................................... 100
Sodium Carbonate...........................................................................................................................100
9....................................................................................................................................................... 100
Vinegar............................................................................................................................................ 100
4....................................................................................................................................................... 100
SOME SUMMARY NOTES.................................................................................................................101
ACID CHEMISTRY REVISION ACTIVITIES...................................................................................102
Rates of Reaction............................................................................................................................ 105
Fill in the blanks below.................................................................................................................... 105
For two particles to react they must come into contact (__________). Not all collisions result in a
b t th f f lli i ill i th t f ti
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Achievement Standard
Subject Reference Science 1.5
Title Demonstrate an understanding of aspects of acidsand bases
Level 1 Credits 4 Assessment External
Subfield Science
Domain Science Core
Status Status date
Planned review date Date version published
This achievement standard involves demonstrating an understanding of atomic structure, particletheory and rates of reaction relating to acids and base properties, uses and reactions.
Achievement Criteria
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2 Aspects of acids and bases will be selected from:
Atomic structure
electron arrangement of atoms and monatomic ions of the first 20 elements (a periodictable will be provided)
isotopes
ionic bonding
names and formulae of ionic compounds using a given table of ions.
Rates of reaction and particle theory.
3 The relationship to acids and bases will be selected from:
Properties
pH and effects on indicators
acids release hydrogen ions in water.
Reactions of acids with bases to form salts.
Uses
neutralisation
carbon dioxide formation
salt formation.
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OBJECTIVES
At the end of this unit you should be able to:
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Recognise the symbols for the first 20 elements plus iron, copper,zinc, silver, gold, and mercury
State the parts of an atom
Show how atomic number and mass number relate to the particles inan atom
Give the electron arrangement of atoms or ions of the first 20elements
Explain the atomic structure of isotopes and relate this to theirphysical properties
Explain why the elements are arranged as they are in the periodictable.
Write ionic formula for AB, A2B or AB2 salts, including the use ofpolyatomic ions.
Write balanced equations if given word equations.
Explain particle theory and reaction rates and the effect ofincreasing concentration, temperature and surface area.
W it b l d ti f ti f N C M Al A F Pb
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Discuss and write balanced equations for reactions of HCl, H2SO4,HNO3, carbonates and hydrogen carbonates
USEFUL WEB PAGES
BestChoice Really aimed at Y12, 13 and university students, but well worth checking out.
Contains tutorials and practice questions.http://www.bestchoice.net.nz/
Chemistry revision Aimed at Y12 & 13, but worth investigatinghttp://www.chemguide.co.uk/index.html#top
Studyit You can look up the standard you are sitting has lots of revision sites to helpand a question and answer forum if you go to communicate
http://www.studyit.org.nz/
NZQA Look at past papers and answer scheduleshttp://www.nzqa.govt.nz/
Rates of reaction http://www.absorblearning.com/chemistry/demo/units/LR1501.html
http://www.bestchoice.net.nz/http://www.chemguide.co.uk/index.html#tophttp://www.studyit.org.nz/http://www.nzqa.govt.nz/http://www.absorblearning.com/chemistry/demo/units/LR1501.htmlhttp://www.bestchoice.net.nz/http://www.chemguide.co.uk/index.html#tophttp://www.studyit.org.nz/http://www.nzqa.govt.nz/http://www.absorblearning.com/chemistry/demo/units/LR1501.html -
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EXAMINERS REPORT 2009
ACHIEVEMENTCandidates who were awarded Achievement commonly:
recognised that neutral atoms have the same number of electrons and protons
stated protons and neutrons were the main contributors to atomic mass
wrote correct word equations detailing acid-base reactions recalled observations in metal-oxygen and neutralisation reactions
recognised that universal indicator can be used to test neutrality in a solution byturning green at pH 7.
NOT ACHIEVEDCandidates who were assessed as Not Achieved commonly:
did not recognise the mass and charge of protons, neutrons and electrons
did not state electron configurations
related the neutrality of an atom to gain or loss of electrons
stated that acid-base reactions gave off hydrogen.
ACHIEVEMENT WITH MERITIn addition to Achievement, candidates who were awarded Merit commonly:
showed that they knew that the mass of an electron is negligible
id tifi d t l t ith th t i b h i th
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THE MOST IMPORTANT TABLE IN CHEMISTRY..THE PERIODIC TABLE
St Marys College 19
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1 2
Atomic
Number
18
1
H
1.00
8
Atomic Mass 13 14 15 16
17
2
He
4
3
Li
7
4
Be
9
5
B
11
6
C
12
7
N
14
8
O
16
9
F
19
10
Ne
20
11
Na
23
12
Mg
24
3 4 5 6 7 8 9 10 11
12
13
Al
27
14
Si
28
15
P
31
16
S
32
17
Cl
35.5
18
Ar
40
19
K
39
20
Ca
40
21
Sc
45
22
Ti
48
23
V
51
24
Cr
52
25
Mn
55
26
Fe
56
27
Co
59
28
Ni
59
29
Cu
63.5
30
Zn
65
31
Ga
70
32
Ge
73
33
As
75
34
Se
79
35
Br
80
36
Kr
84
37
Rb
85
38
Sr
88
39
Y
89
40
Zr
91
41
Nb
93
42
Mo
96
43
Tc
98
44
Ru
101
45
Rh
103
46
Pd
107
47
Ag
108
48
Cd
112
49
In
115
50
Sn
119
51
Sb
122
52
Te
128
53
I
127
54
Xe
131
55
Cs
133
56
Ba
137
71
Lu
175
72
Hf
179
73
Ta
181
74
W
184
75
Re
186
76
Os
190
77
Ir
192
78
Pt
195
79
Au
197
80
Hg
201
81
Tl
204
82
Pb
207
83
Bi
209
84
Po
209
85
At
210
86
Rn
222
Table of Ions
+1 +2 +3 3 2 1
NH4 Ca2+ Al3+ O2 OH
Na+ Mg2+ Fe3+ S2 Cl
K+ Cu2+ CO32 NO3
Ag+ Pb2+ SO42 HCO3
H+ Fe2+
Ba2+
Zn2+
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NOTE: This page for interest only, it is not part of your achievement standard
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ALTERNATIVE PERIODIC TABLES
Zmaczynskis Triangular periodic table
Stowes Physicists periodic table
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Current Organisation of the Elements in the
Periodic TableSeveral trends are responsible for the order and placement of the elements into this odd shapedperiodic table.
The periods (rows) go across the periodic table. The first period only contains hydrogen and helium.The second contains Li, Be, B, C, N, O, F and Ne and so on.
The reason they are called periods, is that when the elements are places in the order they appear,
characteristics tend to repeat periodically to form groups of elements.
Groups of elements are aligned vertically (columns). These groups are also called families, becausethe elements found above and below one another have very similar properties.
Group I The alkali metals
Group II The alkali earth metals
Groups III XII The transition metals
Group 17 The halogens
Group 18 The noble gases
Another way that elements are grouped is into metals and non-metals. You often will see a staircaseline across the table to denote where the divide is. Transfer the line below to your main periodictable. Label the metals to the left and non-metals to the right.
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ELEMENT NAMES AND SYMBOLS
Name Symbol Name Symbol
Hydrogen H He
Lithium Phosphorous
Be Sulfur
B ClCarbon Ar
N Potassium
Oxygen Ca
F Iron
Ne Cu
Sodium Au
Mg Ag
Aluminium Mercury
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+++
OOOO
ee
THE STRUCTURE OF THE ATOM
A SHORT HISTORYIn 400BC, Democritus (another Greek philosopher) believed that atoms were small spheres, ofwhich everything was made. Aristotle thought this was rubbish and everybody believed Aristotle!!!
In 1904 JJ Thompson discovered the electron and proposed the plum pudding model of the atom.
In 1911 Ernest Rutherford (a New Zealander) proposed the Rutherford model. He said that all theprotons and neutrons were in the middle of the atom and the electrons floated randomly around this.
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In summary:
The main parts of the atom are Nucleus (where protons and electrons are found)
Energy levels / orbitals / valence shells (Where electrons are found)
Use the labels above to label the atom below.
Complete the table:
+++
oooo
e
e
e
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On the periodic table, information is given that allows us to work out how many protons, neutrons andelectrons an element has. All we need to know is the mass number and atomic number.
The elements look a bit like this on the periodic table.
The atomic number tells us how many protons are in an atom.
The mass number tells us the total number of protons and neutrons.
If the atom is neutral, then the number of protons is equal to the number of electrons.
Example calculation
Work out the number of protons, electrons and neutrons for the atom below.
Tells us there that
Tells us there are Protons + Neutrons =23
3
Li7
The larger number is calledthe mass number.
It is massive!
The smallernumber iscalled the
atomicnumber.
11
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Having a different number of neutrons results in different massnumbers, such as isotopes of carbon
12
6 C and14
6 C. They have
the same number of electrons so their chemical properties areidentical.
Some isotopes are unstable and are radioactive. Thismeans they decay spontaneously by emitting sub-atomicparticles and radiation from the nucleus. Radioactiveisotopes have many uses including the treatment ofcancer, in the dating of fossils and in industry todetermine the thickness of paper.
Relative atomic mass (Ar)
This is the mass of an atom compared to the mass of the12
6 C isotope, which is arbitrarily given a
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c. An isotope and explain why isotopes have similar chemical properties.
___________________________________________________________________________
______________________________________________________________________________________________________________________________________________________
2. Cl 35
17
has ___ neutrons; Cl37
17 has ___ neutrons.
On Earth there is ____% Cl 35
17
and ___%Cl37
17 making the relative atomic mass of Cl
35.5.
3. There is B11
5 and B10
5 :
How many protons in B11
5 and B10
5 ? ___________________________________
If the atoms were half B-11 and half B-10 then the mass number would be ___.
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1) 34X 2) 34X 3) 36X
16 14 14
7. Explain why atoms of14
6 C and N14
7 have the same mass.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
8. Potassium-40 (40K) is used to date very old rocks. Potassium also exists as 39K and 41K. Theatomic mass on the periodic table is 39.1. Explain how potassium can exist as these three isotopesand discuss any conclusion that can be drawn from the data given.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
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Use your Periodic table on page 4 to complete the table: The first one has been done for you.
Symbol Name Mass
No.
Atomic
No.
No.
p
No.
n
No.
e
H Hydrogen 1 1 1 0 1
2
Lithium
4
5
C
Nitrogen
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ELECTRON CONFIGURATION
As mentioned earlier, the way that the particles are arranged in an atom, determines what that atom
is. So it is important for us to know about the arrangements of atoms.
It is the electrons and mostly the valence (electrons in the outside energy level), electrons thatdetermine an elements chemical reactivity.
The electron configuration is how the electrons are arranged in the energy levels.
The first energy level can hold a maximum of two electrons and all other energy levels can hold amaximum of eight electrons.
When working out how the electrons are arranged it is important that you fill up the inside energylevels first. (They are the energy levels with the lowest energy.)
Example
Draw an atom of Boron.
Number of protons =5 Number of electrons = 5 Number of neutrons = 6
(The electrons are represented by Xs)
xx
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Symbol No
p+
No
n0
No
e-
Atomic (Bohr) Diagram
Na
Electron configuration:
C
Electron configuration:
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Drawing Bohr Diagrams Draw Bohr diagrams for the first 20 elements.
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IONS
Up until now, we have examined atoms, which are neutrally charged. Atoms always have equalnumbers of protons and electrons. While the number of protons defines the properties of the elementand does not change, atoms can gain and lose electrons. When this happens, there is anunbalanced charge on the overall element and it is thus called an ion.
Metals have a tendency to lose electrons during chemical reactions. This leaves them with moreprotons (+) than electrons (-). The charge on the metal ion is always positive.
Non-metals have a tendency to gain electrons during chemical reactions. This leaves them withmore electrons (-) than protons (+). The charge on the non-metal ion is always negative. To namenon-metal ions we use the element name and change the end to -ide.
Some atoms change their names when they become ions. Here are the ones you need to know.Notice, they all end in IDE.
Atom Ion Symbol Ion Name
Oxygen O2- Oxide
Fluorine F- Fluoride
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Electron Arrangement of Ions
Just as you wrote the electron configuration for the elements on the periodic table, you can writeelectron configurations for the ions of those elements.
e.g. Al = 2,8,3 Al3+ = [2,8]+
(Notice that the aluminium ion has lost 3 electrons and so becomes positive.)
Fill in the table below with the correct electron configurations. Neutral atoms and charged ions are
called species
Species Arrangement Species Arrangement
Li P3-
Mg K+
Al Ca
2+
Cl- N
O2- S
MORE PRACTICE
Now try these.
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PREDICTING THE CHARGE ON IONS
You should be asking what is the advantage to neutral atoms becoming charged?
Well, in order to be most stable, atoms require a full valence shell (outside energy level). Only thenoble gases have full outside energy levels, and so are the only truly stable elements. All otherelements will either donate or seek electrons from other atoms in an effort to become stable.
It is this exchange of electrons that occurs when chemicals react with one another. It also explainswhy the noble gases do not react.
In order to predict the charge on the ion formed by any element, it is first necessary to look at thenumber of valence electrons found in the outer energy level of a neutral atom.
If an element has less than 4 electrons in its valance shell then it will lose electrons.
If an element has more than 4 electrons in its valance shell then it will gain electrons.
The element gains or loses enough electrons to fill up its outside energy level.
Fill in the electron arrangements and the number of electrons gained or lost.
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Forming Cations:
Consider Magnesium (2,8,2).
It needs to give away 2 electrons to make its valence shell full. (Think of it like this, when a shell isempty, it disappears.)
Therefore if you look at the structure of magnesium. It already has 12 protons and 12 electrons.
As before we could write out the protons as + and the electrons as like this.
If magnesium gives away two electrons to make its valance shell full then it will look like this.
+++++++ ++++ +
- - - - - - - - - -
++++++++++++
- - - - - - - - - - - -
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Forming Anions:
Consider sulfur (2,8,6) It already has 16 protons and 16 electrons.We could write out the protons as + and the electrons as like this.
All the electrons (that are negatively charged) cancel with the protons (that are positively charged). So theatom is neutral.
If sulfur gains another two electrons to make its valance shell full then it will look like this.
It has two extra electrons, that dont cancel out with the protons. So the atom becomes an ion with a
+++++++ ++++ ++ +++
- - - - - - - - - - - - - - - - - -
++++++++++++++++
- - - - - - - - - - - - - - - -
- = 0
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ATOMS neutral (no charge)
ELEMENTS NUCLEUS
COMPOUNDS PERIODIC TABLE
OXYGEN METALS
WATER NON METALS
CARBON DIOXIDE LEFT-HAND SIDE
NITROGEN RIGHT-HAND SIDE
PROTONS ATOMIC NUMBER
NEUTRONS O2
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This page has been left blank deliberately
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The patterns are:
So, by looking at the periodic table. you can cheat and find out what kind of ion an atom will become!
H11 He2
4
Li37 Be4
9
Transition
metals
B511 C612 N
714 O
816 F
919 Ne
1020
Na1123 Mg1224 Al1327 Si1428 P1531 S1632 Cl1735.5 Ar1840
K1939 Ca20
40
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16 6 -2
17 7 -1
18 8 0
SECRET MESSAGE
Use the periodic table to decipher this message. Write down the symbols for each element to spell out a
sentence.
Answer
Calcium, Nitrogen, Yttrium, Oxygen, Uranium, Calcium, Technetium, Hydrogen,
Oxygen, Neon, Sulfur, Oxygen, Oxygen, Nitrogen.
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ELEMENT QUIZ
Name
1 A reddish brown metal
2 A green poisonous gas
3 A liquid metal
4 2 inert gases
5 A very heavy metal
6 The most common gas in air
7 A yellow element
8 A metal found in bones
9An element which is black & cheap or colourless &
expensive.
10 A gas which supports burning
11 A space industry metal
12 An element important in computers
13 A metal needed for photosynthesis
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FORMATION OF COMPOUNDS
Compounds form when two or more atoms come together in a fixed ratios by mass.The reasons atoms come together to form compounds are
because they are able to establish greater stability by gaining or losing electrons to fill theirvalence shell
because they are able to establish greater stability by sharing electrons to cooperativelycomplete each of their valence shells.
Ionic Bonding In the first scenario, metals and non-metals come together and electrons are takenfrom the metal and given to the non-metal. As a result a positively charged cation and a negativelycharged anion result. Due to the opposite charges on the two ions they are attracted to one anotherand combine to form a salt. The attractive force between the two oppositely charged ions is called aIONIC BOND.
Ionic compounds consist of many positive and negative ions held together by strong electrostaticforces of attraction.
Electrostatic
forces of
attraction
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Covalent Bonding In the second scenario the outer valence shell of each non-metal atomoverlaps and the shared electrons are considered to belong to both atoms.
Looking at the diatomic elements such as H2, N2, O2, F2, Cl2, Br2, I2 determine how many electronseach pair of atoms mush share. It can be helpful to draw the element symbol with it valenceelectrons surrounding it.
Questions:
Sodium oxide is an ionic compound. Discuss the changes sodium and oxygen goes through tobecome sodium oxide and the bond that holds them together.
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
My name is bond.Covalent bond
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NAMING IONIC COMPOUNDS
Naming ionic compounds is easy. Just name the metal as you would normally and change the endingof the non-metal name to -ide to show that the elements are chemically bonded together.
So NaCl goes from being called sodium and chlorine to SODIUM CHLOR IDE .
Name these compoundsMgCl2__________________________________
K2O _________________________________
AlF3 _________________________________
Li2S _________________________________
FORMATION OF IONIC COMPOUNDS
When an ion has a charge it is electrostatically attracted to an ion with the opposite charge. Positivesattract negatives and vice versa. They therefore tend to stick together and become an ioniccompound.
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If the ions have different numbers of charges, e.g. Na+ and O2-, then you have to do THE DROP ANDSWAP!
Na+ O2-
Na1O2
Na2O
Step 1: Work out the ion charge
Step 2: Drop the numbers down tothe bottom line
Step 3: Swap the numbers overand delete any 1s.
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Complete the table below.
Name Positive Ion Negative Ion Formula
Lithium oxide Li+ O2- Li2O
Potassium oxide
Magnesium chloride
Iron (II) sulfide
Aluminium oxideCalcium chloride
Magnesium oxide
Iron (III) oxide
Copper chloride
Calcium oxide
Look at the formulae below and name the compounds.
Na2S_______________________ AlCl3____________________
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POLYATOMIC IONS
These are ions made up of two or more atoms. You need to learn their formulae, their charges and
their names! (Although in the exam you will be given a table of ions, but there will be no names onit.)
Name Symbol
Hydroxide OH-
Carbonate CO32-
Hydrogen Carbonate / Bicarbonate HCO3-
Nitrate NO3-
Sulfate SO42-
Ammonium NH4+
When using polyatomic ions you write formulae in exactly the same way. i.e using the drop n swap.
e.g Lithium Carbonate
Li+ and CO32-
Li2CO3
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For example:
+1 2-
Na CO3
= Na2(CO3) but Na2CO3 is just fine without the brackets
+3 2-
Al SO4
= Al2(SO4)3 and the brackets are necessary because Al2SO43 is wrong!It is impossible to fit 43 oxygens on to the two aluminium atoms!!!
So you have to put the polyatomic ion in brackets.
Al2(SO4)3 is the correct formula. This tells you that there are 3groups of sulfate ions attached to the two aluminium ions.
Try these:
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WRITING EQUATIONS
To write equations you need to work out the formula of each substance in the equation.e.g Copper + Chlorine Copper chloride
Cu + Cl2 CuCl2
NOTE: All the gas elements H2,N2, O2, F2, Cl2 exist as diatomicmolecules when in the elemental form. So, whenever you see one ofthe elements above, you have to write them as a diatomic molecule.
Try these
1. Sodium + Chlorine Sodium chloride
2. Calcium + Oxygen Calcium oxide
Balancing Equations:
Equations are written to show how elements are rearranged during chemical reactions to form newsubstances.
The substances on the left side of the reaction are called reactants and the substances on the right
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RULES FOR BALANCING EQUATIONS
1. Write out the reactants and products in symbol form (drop and swap!)
2. Balance metal ions first
3. Balance non metal ions including polyatomic ions
4. Balance for hydrogen
5. Balance for oxygen
6. Double check that steps 2 5 have not thrown off previous balancing
Eg. Use the word equation to write and balance the following equations.
Hydrochloric acid + lithium hydroxide water + lithium chloride
Write and Balance These Equations
1. Calcium hydroxide and hydrochloric acid Calcium chloride + water
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8. Sodium carbonate + hydrochloric acid sodium chloride + water + carbon dioxide
9. Silver nitrate + Calcium chloride silver chloride + Calcium nitrate
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Y10 REVISION OF METALS:
All metals have certain properties.
They are shiny
They conduct electricity
They conduct heat
They are ductile (can be pulled into wires)
They are malleable (can be hammered into thin sheets or bent intoshape)
They are sonorous (if you beat them with a hammer, they make a
ringing sound!!!)
Non-metals may show some of these properties, but not all of them.
PRACTICAL 1
Aim To test the physical properties of metals and non-metals
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Conclusion
Which of the substances are metals?
________________________________________________________________________________
________________________________________________________________________________
Questions
1. Why are some metals dull on the surface but shiny underneath?
________________________________________________________________________________________________________________________________________________________________
REACTIONS OF METALS -Chemical Properties
Atoms of a metal react by losing electrons to form positively charged ions (cations).
Elements in Group 1 of the periodic table form ions with a charge of +1, those in Group 2 form ions
M2+ etc.
a) Reaction of metals with oxygen (air)
Reactive metals react with oxygen, O2, to form metal oxides. For example
zinc + oxygen zinc oxide
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When this oxidation reaction (corrosion) occurs the surface of the metal changes from shiny to dull.In the case of zinc oxide it is a white powder.
Very reactive metals such as sodium and potassium react spontaneously and are therefore stored in
oil. Iron reacts only slowly (the corrosion called rusting takes several weeks).
Aluminium metal rapidly reacts with oxygen in the air to form a surface coating of aluminium oxide.This is what protects aluminium objects from corrosion e.g. aluminium cans and boats.
Copper is an unreactive metal and only forms copper oxide very slowly. Copper oxide is a blackpowder so the surface of the copper slowly darkens. If the metal is heated in air then it goes darkmuch more quickly.
Gold is so unreactive that it remains shiny for centuries.
Exercise
Dry ice (solid CO2) is used in fire extinguishers, but if burning Mg ribbon is placed inside a block ofdry ice it continues to burn with a bright glow and afterwards there is a lot of black soot left. Using abalanced equation explain these observations.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
b) Reaction of metals with water
Only reactive metals will react with cold water at an observable rate Metals like iron react slowly
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Exercises
1) When sodiumis placed in water it often fizzes violently, flames are observed and an explosionoccurs. Following the reaction the water turns litmus blue. Carefully explain these observations.
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
2)Complete the following word equations for reactions.
Beneath each equation write the corresponding balanced equation for the reaction.
a) potassium + water _________________ + ______________
b) ___________ + ___________
aluminium hydroxide + hydrogen
c) Magnesium + water __________________ + ___________________
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Write the word equations for the following metals reacting with acids. If you feel confident trywriting the symbol equation as well.
Common Acids to help you
Hydrochloric acid HClSulfuric acid H2SO4Nitric acid HNO3Carbonic acid H2CO3Ethanoic acid (vinegar) CH3COOH
(Which element do all these acids have in common?)
1. Potassium and Hydrochloric Acid
2. Calcium and Sulfuric Acid
3. Magnesium and Nitric acid
Johny was a chemists son, butJohny is no more. What Johnythought was H2O was H2SO4!
What happened to Johny??
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Aim: To observe the reaction of metals with acid
Method:1. Half fill a beaker with water and put it over a Bunsen burner to boil for later on.2. Put a finger of acid in a test tube and add a small piece of metal.3. If it fizzes, put your thumb over the end of the test tube to collect the gas. When you feel
pressure release the gas into a Bunsen flame.4. Repeat for each Metal.5. For the metals that did not react, place their test tubes in the boiling water.6. Assign a reactivity number to each metal.
Results
Metal Acid reaction Gas Reactivity
Fe
Zn
Cu
Al
In this experiment you will investigate the reaction of metals withacid. You will then attempt to rank the metals in order of their
reactivity. The most reactive at the top.
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1. Beryllium + Hydrochloric acid
2. Magnesium + sulfuric acid
3. Sodium + Sulfuric acid
4. Calcium + Hydrochloric acid
Challenge:
5. Iron (III) + Sulfuric acid
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ACIDS AND BASES
The reactions you need to know are:
Acid + Base Salt + Water
Acid + Carbonate Salt + Water + Carbon dioxide
Acid + Hydrogen carbonate Salt + Water + Carbon dioxide
Acid + Metal Salt + Hydrogen
ACIDSAcids release hydrogen ions (H+) in water. It is the reaction of these hydrogen ions that make up thetypical reactions of acids.
Some mineral acids you should know.Hydrochloric acid HClSulfuric acid H2SO4Nitric acid HNO3
Some organic acids that you should know areEthanoic acid CH3COOH Vinegar Citric acid Oranges and lemonsTartaric GrapesLactic Milk
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3. If you assume that the formula for citric acid is HCit, and baking powder is NaHCO3, write theformula for the reaction occurring in your bath.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________Tip HCit splits into the ions H+ and Cit-.
STRONG AND WEAK ACIDS
A strong acid will give all its H+ ions up. In otherwords it splits up completely.
This is called complete dissociation. Most mineralacids are strong acids and will split up completely.They are said to completely dissociate.
A weak acid will not give all its H+
up. In otherwords it does not split up completely. Some of theacid molecule remains whole. This is called partialdissociation. Most organic acids, such as ethanoicacid, are weak acids.
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PRACTICAL 4
You are going to use a pH meter to test some different acids and bases.
NOTE:
The stronger the acid the lower the pH number on the meter will be.
The stronger the base, the higher the pH number on the meter will be.
Name of Acid pH meter reading Strong or weak
Acid or base?
Ethanoic Acid
Sulfuric Acid
Hexanoic Acid
Hydrochloric acid
Ammonia
Sodium bicarbonate
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0.1 mol L-1 Dilute acid
10 mol L-1 Concentrated acid
Practical 5: pH scale
In this experiment you will prepare a series of solutions by dilution. Each solution approximates to apH number. You will then confirm what you have done by using Universal Indicator.
You can make really concentrated Raro byputting just a little water with the packet of
Raro.
In the really concentrated Raro there is lots ofRaro particles, and not much water. (high moll-1)
If you add lots of water, you get dilute Raro(the way you have it at camp!), this means notmuch Raro and lots of water. (low moll-1)
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Colour in the test tubes below.
NEUTRALISATION
Acids can be neutralised by a base. That means that the hydroxide ions (OH-) in the base react withall the H+ ions to produce water (which is neutral).
Eg H+ Cl- + Na+ + OH- NaCl + H2O
1 2 3 4 5 6 7 8 910
11
12
13
14
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These reactions between acids and bases
can be considered a type of double
replacement reaction where essentially
the H+ ions from an acid combine with theOH from a base to produce water
(leaving the other two ions to form a
metal salt).
acid + base water + metal saltTo obtain a solid sample of the metal salt the water has to be evaporated.
In the laboratory, a neutralisation reaction is commonly used as a method for producing crystals of ametal salt. A sample of black copper oxide, CuO, is added to sulfuric acid and, with heating, a bluesolution of copper sulfate will form. Excess CuO is filtered off, the water is evaporated from the blue
solution and the copper sulfate solid will separate out.
Overall the word equation for these Neutralisation reactions can be written:
metal oxide + acid metal salt + wateror
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Add sodium hydroxide (NaOH) drop by drop until you have a neutral solution.
Pour the solution back into the measuring cylinder. Measure how much extra you have over theoriginal 10ml this is the amount of sodium hydroxide you have added.
Make a neutral solution by measuring out 10 ml of HCl and adding the correct amount of NaOH.
Heat the solution until half the water has boiled off.
Leave on the windowsill overnight.
Conclusion
When universal indicator solution is red, this shows that there are more ___________ ions than_______________ ions. The solution is acidic.
When universal indicator solution is blue, this shows that there are more _____________ ions than______________ ions. The solution is basic.
When universal indicator solution is green, this shows that
___________________________________________________________ . The solution is neutral.
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PRACTICAL 7: WHICH IS MORE ACIDIC?
How acidic something is can be determined by carrying out a neutralisation reaction in the presenceof an indicator.
Add universal indicator to an acid and it will turn red. Slowly add base to the acid and as you use upthe acid (as shown in the reaction below) the indicator will change colour. When the indicator staysgreen, then you know it is a neutral solution and you have used up all the acid.
HCl + NaOH NaCl + H2O
If whilst you are carrying out this test, you measure the amount of base that you use, you will knowwhich substance is more acidic.
AIM To see which drink is more acidic.
HYPOTHESIS:
_____________________________________________
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Reactions of metal carbonates or metal hydrogen carbonates with acids(Neutralisation)
Overall the word equation for the reaction between metal carbonate and acid is
metal carbonate + acid metal salt + water + carbon dioxide
or
metal hydrogen carbonate + acid metal salt + water + carbon dioxide
Metal carbonates are basic because they react with, and neutralise, acids.
Sodium, magnesium and calcium carbonates are all white, but copper carbonate is green.
Different forms of calcium carbonate are found as chalk, limestone and marble. All of them react inthe same way. Calcium carbonate does not dissolve in pure, distilled water. It does howeverdissolve in water in which there is dissolved CO2, forming a solution of calcium hydrogen carbonatewhich is soluble.
CaCO3(s) + H2O(l) + CO2(g) Ca(HCO3)2(aq)
The Ca(HCO3)2(aq) could also be written as Ca2+(aq) + HCO3
(aq)showing that the ionic solid is dissolved in the water. Undergroundlimestone caves (e g Waitomo) are caused by the dissolving of CaCO3 due
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statues made from limestone or marble (chemical formula ________) are destroyed by
_____ rain as the _____ reacts with the calcium carbonate producing ______,_______ and
a soluble _______.
a solution of b_____ s_______ can be used to neutralise the acid in a bee sting.
When an acid is added to either a solid sample or a solution of a metal carbonate or metal hydrogencarbonate, there will be fizzing (effervescence). Thegas given off is carbon dioxide, CO2.
Carbon dioxide gas can be collected by downwarddelivery or upward displacement of air (because theCO2 is denser than air).
CO2 can also be collected by downward displacementof water, although it is reasonably soluble in water(particularly when under pressure).
At the end of reaction a solution of calcium chloride isleft in the flask. Balance the following:
CaCO3 + HCl _______ + _______ + ________
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PRACTICAL 8
AIM: To see if CO2 forms an acidic, basic or neutral solution.
METHOD
1. Fill a third of a boiling tube with water
2. Add 5 drops of universal indicator and note the colour.
3. Blow gently through the straw, with exhaled breath, in to the solution in the boiling tube.
RESULTSThe water started off with a pH of ______________, after breathing CO2 into it for a while it had a pH
of ______________.
QUESTIONS
1. What type of solution is formed when CO2 dissolves in water?________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
2. What implications could this have on animals living in small ponds?
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pH SCALE
A pH scale is used to measure how acidic or basic a substance is. pH is a measure of H+
concentration.
1 7 14
Acidic Neutral Basic/Alkali
When all of the H+ ions have reacted with the base, the solution is said to be neutral. This means thatthe pH measurement will be 7 on the pH scale. (The middle, halfway between acid and base)
Eg.
HCl + NaOH NaCl + H2OpH 2 10 7 7
In order to compare how acidic substances are, we need to compare substances that all have thesame concentration.
The more acidic something is, the more fully it will give off its H+ ions and the lower its pH number.The more basic something is, the higher its pH number.
Add these substances to the pH scale above:
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PRACTICAL 10
AIM: To determine whether household substances are acidic, basic or neutral
METHOD:
1. Pour a small amount (a finger) of each household chemical in to a separate test tube. Makesure you know which is which.
2. Add 2-3 drops of universal indicator to each test tube.
3. Record the colour the indicator goes in your results table.
RESULTS
CHEMICAL COLOUR INUI
pH ACID, BASEOR
NEUTRAL
WEAK ORSTRONG
Soap
Lemon Juice
Vinegar
Baking soda
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3. Which household substances were basic?
4. Which of these bases were strong bases?
5. Which household substances were neutral?
INDICATORS
We use indicators to measure the amount of H+ ions that are in a solution. Indicators are chemicalsthat change colour when going from more acid to more basic conditions and vice versa. Eachindicator changes colour at a specific pH.
You have most certainly used litmus paper as a general indicator in the lab.
LITMUS (paper or liquid) is an acid base indicator that lets us know if we have an acid or base, nothow strong the acid or base are.
Bases turn red litmus ____________________ Remember: RBB Red Base Blue!
Acids turn blue litmus ____________________ Remember: BAR Blue Acid Red!
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RATES OF REACTION
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Some reactions are fast and some are slow. When vinegar is added to baking soda, the reaction isfast and carbon dioxide is rapidly formed. Concrete setting is quite a slow reaction (taking manyhours), while rusting is a very slow reaction (taking several weeks or years).
Reaction rate describes how fast or slow a reaction is. Rate can be measured by finding out how fasta reactant is used up, or how fast a product is formed.
This can be done by measuring
how fast a colour change occurs (if one of the reactants or products is coloured)
the volume of gas produced after various times if one of the products is a gas
the decrease in mass with time if one of the products is lost as a gas.
Depending on the speed of the reaction, measurements can be made every few seconds, minutes,hours or even days.
Consider the reaction of magnesium with hydrochloric acid to produce hydrogen gas and a solution ofmagnesium chloride.
magnesium + hydrochloric acid magnesium chloride + hydrogen
You could measure the rate of this reaction by measuring either:
the amount of magnesium used up per minute or
the amount of hydrochloric acid used up per minute or
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Answer the following questions from the graph.
From the graph above, how can you tell when the reaction is over?________________________________________________________________________________
____________________________________________________________________________
____
From the graph answer the following questions.
How much hydrogen is produced in
(i) 2.5 minutes? ____________________
(ii) 4.5 minutes? ___________________
How many minutes does it take to produce
(iii) 10 mL of hydrogen? _______________
(iv) 20 mL of hydrogen? ______________
(v) What is the rate of reaction in the fourth minute? _________
Note that in carrying out a reaction of a metal with an acid, the metal must first of all be rubbed with
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Explaining Rates using Collision Theory
1. Concentration
As the concentration of a solution increases, the number of dissolved particles increases.Increasing the concentration therefore means there are more particles available forcollisions so that the frequency of collisions will increase. This will increase the rate of thechemical reaction.
A sample of air contains about 20% oxygen gas, most of theremaining 80% being nitrogen gas. This means that in areaction involving oxygen, the reaction done in air will beslower than the same reaction done in oxygen since thelatter has a higher concentration and therefore there aremore frequent collisions between reacting particles.
Think about it this way: If youare in a lolly scrabble the morelollies there are, the more likelyyou are to get one!
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Note these things about the graph:
Curve A is steeper than curve B which tells you that the reaction was faster in A than in B
In A, reaction lasts 60 seconds, in B it lasts for 120 seconds.
The rate of reaction in A is double the rate in B i.e. the rate of reaction has doubled when theconcentration of acid was doubled.
Both reactions produced 60 mL of hydrogen. The volume of gas is the same because bothexperiments used the same amount of magnesium, and excess acid.
Practical 11: How concentration affects rate of reaction
AIM: To see if concentration affects reaction rate.
HYPOTHESIS: If the concentration of HCl is increased, the calcium carbonate will dissolve more
quickly.
METHOD:1. Note down the mass of your test tube.2. Add a scoop of calcium carbonate to your test tube.3. Re-weigh the test tube and do a subtraction to find out what mass of calcium carbonate you
added. Note this number down.
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3. Temperature
When temperature is increased the particles gain kinetic energy and this has two effects. Firstly theymove faster and therefore collide with other particles more often. Secondly since the particles
have more energy, it is more likely that the collisions will have enough energy to result in areaction (ie a larger proportion of the collisions will exceed the activation energy so that reactionoccurs). Thus increasing the temperature results in both an increase in the frequency ofcollisions and in the effectiveness of the collisions. This leads to an increase in reaction rate
On the axes below draw a second curve showing the decrease in mass of reactants in a secondexperiment with the same amount of all reactants at a higher temperature
Mass of
Reactants/g
Time/min
Exercise
The table below gives the result of six experiments involving the reaction between zinc andhydrochloric acid. In all experiments 0.2 g of zinc was used together with the same volume ofacid.
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Exercises
1. An experiment was carried out between magnesium and an excess of hydrochloric acid. Theresults are shown below.
Time/ min 0 1 2 3 4 5 6
Volume of hydrogen
/ mL
0 22 34 39 40 40 40
Plot these results on a graph.
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c. In which experiment was the reaction
fastest? ________
slowest? ________
d. In which experiment was the sodium thiosulfate most concentrated? How can you tell?________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
e. Name 3 variables that need to be controlled.
__________________________________________________________________________
f. Write a suitable conclusion for the experiment based on the results above.
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
g. Suggest 2 ways of speeding up this reaction.________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
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PUTTING IT ALL TOGETHER
Fill in the blanks.
pH is a measure of how A_______________________ or B_____________________ (alkaline) a
solution is.
Strong acids release high concentrations of ______________________ ions. Weak acids
produce small concentrations of hydrogen ions in solution.
Strong alkalis release high concentrations of __________________________ ions in
solution and weak alkalis release small concentrations of hydroxide _____________ in
solution.
Acidic solutions have a pH of less than ______________
Alkaline solutions have a pH of ___________________ than 7
Neutral solutions have a pH of ______________________
Acids and Bases
T X O D U C E V G B H Y Q S P
R W Z W W Q V Z V X A R M H L
H Y D R O G E N G E M S E G A
S E T A N O B R A C M N E N S
ACID
ALKALI
AMMONIA
ANTACID
BAKING
BASE
CARBONATES
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ACIDS AND METALS
Metal + Acid Salt + Hydrogen
This was covered in the section on metals.
ACIDS AND CARBONATES
Carbonates fizz when they are put into acid. They give off the gas carbon dioxide.
The products of an acid + carbonate reaction are carbon dioxide, water and a salt. The salt dependsupon what the original acid and carbonate were.
e.g.
ZnCO3 + 2HCl CO2 + H2O + ?
In this reaction, if carbon dioxide and water are formed, the only things left are zinc and the chlorideion from the acid. So these two join together to make zinc chloride salt.
ZnCO3 + 2HCl CO2 + H2O + ZnCl2
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USES OF ACIDS AND BASES IN EVERYDAY LIFE
Fill in the table below, referring to the pages numbers listed in the New Directions in Science Book.
Substance Use How it works?
Baking soda
(Sodium HydrogenCarbonate)
Page 58
Baking
Mylanta
Page 67
Antacid
LimestonePage 68
Decay byacid rain
Toothpaste
Page 52
Neutralisesplaqueacid
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SOME SUMMARY NOTES
Acids
Acids are compounds that release hydrogen ions (H+1)in solution.
HCl, H2SO4, HNO3 are the acids listed in the achievement standard but you could also befamiliar with CH3COOH
Acids react with metals, bases and metal carbonates to form SALTS and other products.
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3. acid plus base NEUTRALISATION the H+1 ion of the acid reacts with OH-1 ion of the baseto form a neutral product WATER plus a SALT. During the reaction you should expect to see
a change in the colour of Universal indication or litmus. The SALT you produce is in solutionso the water can be evaporated to produce the solid SALT.
Magnesium hydroxide (in stomach powders / antacids) and HCl
Sodium hydroxide and sulphuric acid
Copper oxide and sulphuric acid
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Rates of Reaction
Fill in the blanks below.
For two particles to react they must come into contact (__________). Not all collisions result in a
___________, but ___________ the frequency of collisions will increase the rate of reaction.
There are 3 ways ___ which it is possible to increase the frequency or effectiveness of collisions
and therefore increase the _____ of reaction.
1.Concentration of solution - if the ______________ is increased the number of reacting particles
__ increased so there will be _____ frequent collisions and a _______ reaction rate.
2. Surface area of a solid - having a more finely divided (more powdered) solid increases the
________ area and this increases the _______ of particles exposed for collisions _____ the
particles in the liquid. This increases the rate of _________.
3. Temperature - As temperature is increased the energy of the reacting __________ increases.
This means they will be moving _______ and collide more ______ and with more _______ .
This means increasing temperature will increase the rate of reaction.
The rate of reaction can _____ be increased by adding __ chemical called a catalyst. This
generally provides an alternate mechanism for the reaction, in which ___________ with less
energy are effective and result in a reaction occurring. A _________ that is effective for one
reaction may have effect in another reaction
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ASSIGNMENT TWO
1. James and Diana placed some magnesium and calcium in water.
a. Write word equations for the reaction of water with Mg and Ca
b. Write balanced equations for the reactions in (a)
2. What would they have seen when they added phenolphthalein to the solutions of metalformed?
3. Write the word equation for burning magnesium.
4. Write a balanced equation for the reaction of lithium with water.
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You are given the symbols below, now try to find the corresponding elemental name.
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Elementary Fun
C U T D M F N C J M W M O G K I L N A G N O P M A M M V B U P Z A S J D H D G U Z N M N C Y O C M TD L U U U R W A R V A T U X E W C V I E V B M O U U U M X O W N C P D K A L X E O U E D H I Q Z U T
H Q P B I A F E S H N G I I Y Z M P O T F K X U C I U I T P T P N L A B Z O G R I G W L R T K O I F
P O O G N N X S P A T Y N Z N A I N T D R P P I I V N A H I A R G O N L M G O L O Y X Z O T H M T Y
U X X G I C U I S L K V E E M A A O A O I O R A K D S U M T B A T E L S L B L R O B W H M R Q U E T
J N U U L I V U L U K G B D S L T E N B T E G C Z S I O T S E L E N I U M A D C V V C F I I B N T L
E G M X O U C M E M M K C U U I L I E D M H V E I A N R T P O M I R M M H Y D N M W G N C U E I U K
A F P P D M M A X I B E R Y L I U M T A I N U U N Y K L I Z E H O X J T H H O I A Y V P U M I T L N
G W J F A Z H M L N R R J G N C V M C S I N M L R H O D I U M N T R G R Q T A M U Z W H M F N A P O
V H W V G X C W W I M U I M Y D O E N C R W E H I Y P C H T D V Z K P F P I R A O M H G I V S L R B
T E R B I U M I U U F S O D I U M A K U V U T H X U H D U R H K O E K Y R U T H E N I U M V T P A R
A J C F U Q X M N M E O X K J T R E Y L O U B M Z L M V Z N T I V S R R M N X N S U K E N I E O D A
X Y H Y C T G H O E D Z R Q F H L Q U U M Q G I O V B X O D A V U K M R K O P O D E K K G F I B I C
M U I M L H E A D D S T A N Z E C U J S F S H R D M U I R A M A S M U I N E H R M R P O L O N I U ME S E N A G N A M N N R M E I V I S I I F O I R X I K G Y I T T E R B I U M A H T A K M D Y I W M U
B E R E L I U M W P J E A U L U S B U X N N B E W F U X F Z T K B X U T D M U E M D S U F K U A T I
S E F S M U L A T N A T T C I U M C R M E F W V K R T M M M H W W E Y M O Z C I L O I I W Z M E S N
I N M U I M R E F A N Y O S O M U T N B U D R L P G J U U K O G A O S U U H R U B N B T G N L I G O
L I F G N M U I L L A G Y R G V Y N T I N I I I T T I I W H R A Q S R O N I T R N R E N M L S G O T
I M J S S U A W X E N T O K K N M D T K Z I P S G S M Y Z W I Z O A T E J A L E U I E O U U V R Z U
C O C W E I B U N C N H N O R I U U Y V N A N O O O V R V O U R N I T A T T G E N Z J R E T I Z J L
O R O O U N N C N I P B A R I U M T I O U B Q R R M I U D H M I O I H A T Y K F H Q I T P M R B V P
N B B U K I Z A F S J P A Z Z I J J Y N E I P H W U Q C A T U B U C C U X I A Q K U A S U F G K O X
A U A J Q T K F O W F Y J X J Z W V F V A S C J O I E R S M R M D T R O C K N H M P K I S L T T M N
E F L C V C V H S K O S A T E X T C P O Y M A S X D F E P Z M U I D N A C S A E A K N V E U C I U V
E B T O U A P R E P P O C L E N S C M D N V R R Q A O M R U L N W W L T T F Q L H O E V T O L F I J
R I M Z W T R U T K Y W V K J R O Q U A J P U E P N P C I K I Y W C O L N M G S C E Y N R R E F R RH O G N M O L Y B E D E N U M U I N A H T N A L G A V D Y U F G I W N I T H C R Z E Y T L I T R U L
V D V H V R C L B Q K N A L C G O W Y U J S Z A Q V N A M T W U W H U H N M I B P D Z N M N V H C R
U I P I Y P L X U P K G I U W Z S U M R Q O Z E I I C V O T M J T M W W E Z V F I O P G E E F O X X
H He Li Be
B C N O
F Ne Na Mg
Al Si P S
Cl Ar K Ca
Sc Ti V Cr
Mn Fe Co Ni
Cu Zn Ga Ge
As Se Br Kr
Rb Sr Y Zr
Nb Mo Tc Ru
Rh Pd Ag
In Sn Sb Te
I Xe Cs Ba
La Hf Ta W
Re Os Ir Pt
Au Hg Tl Pb
Bi Po At Rn
Fr Ra Ac Ce
Dy Ho Er Tm Yb Lu Th Pa U Np Pu Am Cm Bk Cf Es Fm Md