1 i) acid ii) alkali iii) sour taste iv) soapy feel
2 v) litmus vi) neutral vii) indicator viii) blue ix) hydrangea x) vitamin C
Property
Ions produced in solution H
+
(H
3
O
+
)
Taste Sour
Feel
Electrical conductivity
Burning
Conducts
Acids
OH
-
or O
2-
Bitter
Soapy
Conducts
Bases
Colour of litmus
Common example
Common use
Red
Hydrochloric acid, sulfuric acid
Blue
Sodium hydroxide, ammonia
Food, fertilisers, detergents, cleaning Soap, fertilisers, cleaning products
3a) Solution A is more acidic b) i, ii, iii and iv c) White vinegar is highly acidic d) Baking soda is slightly alkaline
4) Solution C contains both P and Q.
5a) Blue b) Red c) Stay the same
1a) HBr
(s)
+ H
2
O
(l)

H
3
O
+
(aq)
+ Br
-
(aq) b) Ca(OH)
2(s)
+ H
2
O
(l)

Ca
2+
(aq)
+ 2OH
-
(aq)
+ H
2
O
(l) c) HX
(aq)
+ NaOH
(aq)

NaX
(aq)
+ H
2
O
(l) d) HX
(aq)
+ MOH
(aq)

MX
(aq)
+ H
2
O
(l) e) NH
3
+ H
2
O
(l)

NH
4+
(aq)
+ OH
-
(aq)
2a) In general the oxides of non-metals are acidic . The bonding in non-metallic oxides is covalent and slightly polar. b) CO
2(g)
+ H
2
O
(l)

H
2
CO
3(aq) c) In general the oxides of metals are basic . The bonding in metallic oxides is ionic . d) CaO
(s)
+ H
2
SO
4(aq)

CaSO
4(aq)
+ H
2
O
(l) e) Oxides which react with both acids and alkalis are called amphoteric oxides.
3)

4) Low acidity CO

K
2
O

Al
2
O
3

Cl
2
O
7
High acidity
6) After the Industrial Revolution in the early 1800s, there was a large increase in SO
2
emissions. This was changed in the 1950s when emissions were regulated to stop people dying from air pollution. SO
2
is washed out of the atmosphere by rain, preventing a significant build up in atmospheric concentration.
Increasing use of motor vehicles and electricity generation in the 20 th
century has led to an increase in the production of NO x
. Although car and power station emissions are regulated, increasing population means increasing numbers of cars and increasing power production that cancels out the effects of the regulations.
NO and NO
2
are washed out of the atmosphere by rain, preventing a significant build up in atmospheric concentration. N
2
O is not, and as a result its concentration in the atmosphere has increased by well over
30%.
7) 12.2 L
8a) C
2
H
5
OH
(l)
+ 3O
2(g)

2CO
2(g)
+ 3H
2
O
(l) b) 92 g c) 108 mL
9) 3.7 L
10) 44.8 L
1. Unpolluted rain is slightly acidic because atmospheric CO
2
is dissolved in it forming carbonic acid.
2. The main chemicals that contribute to the acids in acid rain include sulfur dioxide, nitrogen dioxide and nitric oxide.
3. Natural sources of acid rain are volcanic eruptions, lightning, bacterial decomposition and forest fires.
Man-made sources are the result of the combustion of fossil fuels – power plants, ore smelting, petroleum refining, motor vehicles, and industrial furnaces.
4. Dry deposition is the process of acidic oxides being deposited directly onto surfaces and then converted to acids when precipitation contact the surface.
5. Acid rain could affect humans through biomagnification of toxic metals through the food chain, by dissolving pipes made of metals that carry drinking water and by being inhaled.
6. 400 000 tons x 907 = 362 800 000 kg = 362 800 000 000g
There’s 1.84g in every mL, so 362 800 000 000 / 1.84 = 197173913043 mL
In every 60 000L pool, so there’s 60 000 000mL
197173913043 / 60 000 000 = 3286 pools
1a) False – For chemical equilibrium to be established the reaction must be reversible. b) True c) False – Le Chatelier’s principle states that if a system at equilibrium is disturbed the system adjusts itself to minimise the disturbance. d) False – For a system to be at equilibrium there may be equal or different amounts of reactants and products. e) True f) True g) False – The solubility of CO
2
decreases as temperature increases. h) True

i) False – An increase in temperature will cause an exothermic reaction at equilibrium to move to the left, absorbing heat. j) False – Removing the cap on a fizzy drink lowers the CO
2
concentration and causes the equilibrium to move to the right releasing more CO
2
.
2ai) Move to the right bi) Move to the right ci) Move to the left di) Move to the right iii) Move to the right ii) Move to the right ii) Move to the left iii) Move to the right iv) Move to the right iv) Move to the right iv) Move to the left iv) Move to the right
3a) The equilibrium would move to the left because 1 mole of gas and a solid takes up less volume than 2 moles of gas, so the equilibrium will move to take up less space. b) The equilibrium will move to the right because the reaction is endothermic. Increasing temperature will move equilibrium to the right because this uses up energy and hence reduces temperature. c) The equilibrium will move to the right to decrease the concentration of C.
4a) Add N
2
and increase pressure would maximise NH
3
production. b) Add O
2
, remove H
2
O and increasing pressure would maximise Cl
2
production.
5a)
Solubility of CO
2
in water
4
3.5
3
2.5
2
1.5
1
0.5
0
0 10 20 30 40
Temperature ( o
C)
50 60 70 b) Approx. 1.4 g/kg H
2
O
6a) Panting removes CO
2(g) from the chicken and so forces the equilibrium to the left. This removes CO
3
2- from the chicken so it is not available for shell building. b) By putting CO
2(aq) into the chicken, the equilibrium will move to the right, increasing the amount of
CO
3
2- available for shell building.

1) D
6) B
2) C
7) B
3) A
8) B
4) C
9) A
5) D
10) B
11a) Hydrogen ion concentration is measured in mol/L and states how many moles of [H
+
] are present in a litre of solution. pH is the log
10
of [H + ] and is used as a simple way of representing the wide range of molarities of acids. It is a logarithmic scale. b) Both strong and weak acids are proton donors, however a strong acid will completely ionise in solution whereas a weak acid will not – acid molecules will be in equilibrium with the ions. c) A hydrogen ion [H
+
] is a bare proton and is not often found. The hydronium ion [H
3
O
+
] is a proton sharing one of the non-bonded electron pairs in a water molecule. [H + ] is often written for convenience. d) pH 5 means a [H
3
O
+
] of 1 x 10
-5
mol/L and is acidic. pH 9 means a [H
3
O
+
] of 1 x 10
-9
mol/L and is basic. e) Both litmus and acid-base indicator give a general indication of pH, however litmus only tells you whether a substance is an acid, base or neutral, while acid-base indicators usually tell you a range of pH for a substance, hence they are more accurate. f) No difference g) pH meters are more accurate than indicator solution however they are usually more expensive. pH meters generally do not interfere with the acidity of a solution as indicators do. h) Concentration gives an indication of the number of acid molecules/ions present in a litre of solution. A lot of molecules is a concentrated solution, few molecules is a dilute solution. The strength of an acid solution depends upon the ability of the acid molecule to ionise in solution. A strong acid ionises completely, a weak acid only ionises partially. i) K w
is the ionic product constant for water. It is a measure of the how many water molecules self-ionise
(ionise with others like themselves) in every litre of water as shown in the following equilibrium:
In one litre of water, [H
+
] = 1 x 10
H
2
O + H
2
O
⇌
H
3
O
+
+ OH
-
-7
mol/L. [OH
-
] also equals 1 x 10
-7
mol/L because for every H
3
O
+ produced, an OH is created. K w
is the product of these:
K w
= [H
+
] x [OH
-
] = 1 x 10
-7
1 x 10
-7
= 1 x 10
-14
mol/L
2
. pH is the log
10
of [H
+
] and is used as a simple way of representing the wide range of molarities of acids. It is a logarithmic scale.
12) concentrated strong acid, dilute strong acid, concentrated weak acid, dilute weak acid
13a) H
2
O + H
2
O
⇌
H
3
O + + OH c) CH
3
COOH + H
2
O
⇌
H
3
O
+
+ CH
3
COO
-
14a) 4.00
15a) 1.0 x 10
-4
mol/L
16a) 0.010 mol/L
17a) 0.10 mol/L b) 2.70 b) 0.03 mol/L b) 4 x 10
-4
mol/L c) 2 x 10
-8
mol/L b) 0.10 mol/L c) 2.52 c) 1.00 b) HBr + H c) 2.5 x 10
-14
2
O
mol/L

H
3
O d) 11.30
+ + Br e) 9.00
18a) From the information given, either student could be correct. From the phenol red indicator, we can see that the pH is 6.8 at the lowest, meaning the solution would be acidic. However the upper limit of pH could be about pH 7, after which point the bromothymol blue would be blue – hence changing the overall colour

of the solution from yellow to green. So the acidity or neutrality of the solution cannot be accurately determined using these indicators. b) Use a pH meter.
19a) HCl 1.00; H
3
PO
4
1.64 b) H
3
PO
4
has a higher pH than HCl because it does not ionise completely in solution, unlike the strong acid
HCl. The number of protons present in the acid does not necessarily reflect its strength.
1a) sour, hydrogen, chemical, oxygen, acids, metallic b) Davy, hydrogen, salts, water c) hydrogen, completely, slightly, hydroxide, aqueous d) proton, acceptor, donates, conjugate, proton, acid, amphiprotic
Species have been omitted from the following for convenience (laziness)
2a) HNO
3
+ H
2
O

H
3
O
+
+ NO
3
b) HF + H
2
O

H
3
O
+
+ F- c) H
2
CO
3
+ H
2
O
⇌
H
3
O
+
+ HCO
3
d) HSO
4
-
+ H
2
O
⇌
H
3
O
+
+ SO
4
2b) HS
-
+ H
2
O
⇌
H
2
S + OH
d) KHCO
3
+ H
2
O
⇌
H
2
CO
3
+ K
+
+ OH
-
3a) NaOH

Na
+
+ OH
c) NH
3
+ H
2
O
⇌
NH
4
+
+ OH
-
4a) NH
3 b) CN
-
5a) HCl b) HCN
6a) acid HCOOH, conjugate base HCOO
b) acid H
2
O
2
, conjugate base HO
2
c) acid HS
-
, conjugate base S
2-
7a) base HS
-
, conjugate acid H
2
S b) base CH
3
O
-
, conjugate acid CH
3
OH c) base PO
4
3, conjugate acid HPO
4
2c) H
2
O c) H
2
PO
4
d) BrO
d) N
2
H
5
+
8a) H
3
C
6
H
5
O
7
+ H
2
O
⇌
H
3
O
+
+ H
2
C
6
H
5
O
7
-
H
2
C
6
H
5
O
7
+ H
2
O
⇌
H
3
O + + HC
6
H
5
O
7
2-
HC
6
H
5
O
7
2-
+ H
2
O
⇌
H
3
O
+
+ C
6
H
5
O
7
3b) H
2
C
4
H
4
O
6
+ H
2
O
⇌
H
3
O
+
+ HC
4
H
4
O
6
-
HC
4
H
4
O
6
-
+ H
2
O
⇌
H
3
O
+
+ C
4
H
4
O
6
2c) HOCl + H
2
O
⇌
H
3
O
+
+ OCl
-
9) HCO
3
+ H
2
O
⇌
H
3
O + + CO
3
2-
HCO
3
-
+ H
2
O
⇌
H
2
CO
3
+ OH
-
base
10a) CH b) NaNO c) KCN d) Na e) NH f) K
2
2
4
3
SO
Br
CO
3
3
COOK
4 acid
K + doesn’t react with water, CH
3
COO + H
2
O
⇌
CH
3
COOH + OH basic
Na
+
doesn’t react with water, NO
3
-
is the conj. base of a strong acid neutral
K
+
doesn’t react with water, CN
-
+ H
2
O
⇌
HCN + OH
-
Na + doesn’t react with water, SO
4
2 is the conj. base of a strong acid basic neutral
NH
4
+
+ H
2
O
⇌
NH
3
+ H
3
O
+
, Br
-
is the conj. base of a strong acid acidic
K
+
doesn’t react with water, CO
3
2-
+ H
2
O
⇌
HCO
3
-
+ OH
basic

1a. False. Neutralisation takes place when an acid and a base react. b. True c. True d. False. The equivalence point of a titration sometimes occurs at pH 7. e. False. In doing a titration one of the solutions used must be a standard solution. f. False. The long graduation tube used in a titration is called a burette. g. True h. False. The indicator used in a titration will depend on the pH of the equivalence point which depends on the pH of the salt formed by neutralisation. i. True
2a and b. Should use a beaker instead of a watch glass so it can be rinsed to get all of the solid into the flask.
The solid should be transferred to the flask and completely dissolved before the flask is filled.
Distilled water should be used to fill the flask instead of tap water.
The bottom, not the top, of the meniscus should sit on the mark.
3ai. It would have diluted it ie. reduced the concentration. ii. It should have been rinsed with the sodium carbonate solution. bi. It would have diluted it ie. reduced the concentration. ii. It should have been rinsed with the hydrochloric acid solution.
4a. 5.1 g
5a. 6.6 L b. 4.8 g b. 0.27 mol/L
6a. 2NaOH
(aq)
+ H
2
SO
4(aq)

Na
2
SO
4(aq)
+ 2H
2
O
(l) b.2.20 x 10
-3
mol c. 4.40 x 10
-3
mol
7. 4.96 mol/L
9a. 1.13 mol/L
8. 73% b. 6.37% (w/w) d. 0.176 mol/L
10. 0.28 L
11a. Strong acid – R, turns litmus red, has a high electrical conductivity b. Strong base – U, turns litmus blue, has a high electrical conductivity c. Weak acid – T, turns litmus red, has a low electrical conductivity d. Weak base – Q, turns litmus blue, has a low electrical conductivity e. Salt – S, no colour change in litmus (neutral salt), has a medium electrical conductivity
12. HCl is a monoprotic acid. There is only one H available to be transferred to the one OH of NaOH for neutralisation.
H
3
PO
4
is a triprotic acid. It has three H’s available to be transferred to each OH of three NaOH for neutralisation. So only 1/3 mole of H
3
PO
4
is needed for every one mole of NaOH.
1a. HCl + Al(OH)
3

AlCl
3
+ H
2
O c. 2 HBr + Ca(OH)
2

CaBr
2
+ H
2
O
5a. conjugate base d. H
2
CO
3 b. CO
2 e. HCO
3
-
6. H
2
PO
4
⇌
HPO
4
2-
+ H
+ b. H
2
SO
4
+ MgO

MgSO
4
+ H
2
O c. acetic acid f. decrease

1.
Series
Alcohols
Alkanoic acids
Functional
Group
-OH
-COOH
General
Formula
R-OH
Intermolecular forces
Hydrogen bonding
Hydrogen bonding
Melting /
Boiling points
High
Solubility in water
Soluble
(decreases with molecular chain length)
Very high Soluble
(decreases with molecular chain length)
C
2
Example
Ethanol
H
5
OH
Propanoic acid
C
4
H
6
O
2
(or
C
3
H
5
COOH)
Esters -COO- Dispersion and dipole-dipole
Low Insoluble
(except for the small ones)
Propyl methanoate
C
4
H
8
O
2
or
HCOOC
3
H
7 d)
2. a) b) e) c) f)
3a. 1-butanol d. pentanoic acid b. 2-hexanol e. ethyl butanoate c. propanoic acid f. methyl pentanoate
4. Alcohols have O-H and so have H-bonding between molecules. They also have C-O and hence have dipole-dipole forces.
Alkanoic acids contain C-O, O-H and C=O bonds that form hydrogen bonds and even more dipole-dipole forces.
Esters only have C-O and C=O, so there’s less hydrogen bonding. They also tend to be larger molecules since they have both an alkanol and an alkanoic acid stuck together.
5a. C
4
H
7
OH + CH
3
COOH

CH
3
COOC
4
H
7
+ H
2
O b. retort stand, reflux condenser, flask butyl ethanoate c. Add distilled water to dissolve the leftover acid and alcohol, shake, then separate with a separating funnel. Add sodium carbonate to completely remove any remaining acid, add an equal volume of distilled water, shake, and separate in a separating funnel. The ester could be further distilled for maximum purity.