1
1
Sodium hydroxide is used to make the red dye alizarin.
Alizarin is soluble in ethanol.
A crystal of alizarin is placed in a beaker of ethanol.
After a few hours, the red colour has spread throughout the beaker.
ethanol
crystal of
alizarin
at the start
after a few hours
Explain these observations using the kinetic particle model.
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[3]
[Total: 3]
2
This question is about halogens.
The table shows some properties of four halogens.
halogen
melting point
in °C
boiling point
in °C
density at room temperature
and pressure
3
in g / cm
chlorine
−101
−35
0.003
bromine
−7
59
3.12
iodine
114
184
astatine
302
6.35
(a) Complete the table by predicting:
•
the density of iodine at room temperature and pressure
•
the boiling point of astatine.
[2]
2
(b) Predict the physical state of bromine at 20 °C.
Give a reason for your answer.
...........................................................................................................................................
...........................................................................................................................................
[2]
[Total: 4]
3
Complete the diagram to show the electron arrangement in a chlorine atom.
Cl
[2]
[Total: 2]
4
Deduce the number of electrons and neutrons in one atom of the isotope of nickel shown.
62
28Ni
number of electrons .................................................................................................................
number of neutrons ..................................................................................................................
[2]
[Total: 2]
3
5
The structures of seven compounds or elements, A, B, C, D, E, F and G, are shown.
A
H
C
B
H
H
C
C
D
P
N
H
N
Cl
Cl
Cl
H
H
H
H
H
C
C
H
H
G
F
E
H
O
O
H
H
C
H
H
H
H
H
C
C
C
H
H
H
State which structure, A, B, C, D, E, F or G, represents an element with a giant covalent structure.
..................................................................................................................................................
[1]
[Total: 1]
6
Potassium is a Group I element.
Potassium combines with sulfur to form an ionic compound, potassium sulfide, K2S.
Give two physical properties of ionic compounds.
1 ...............................................................................................................................................
2 ...............................................................................................................................................
[2]
[Total: 2]
7
Complete the dot-and-cross diagram to show the electron arrangement in a molecule of
phosphorus(III) chloride, PCl3. Show outer shell electrons only.
Cl
P
Cl
Cl
[2]
[Total: 2]
4
8
Potassium is a Group I element.
Potassium combines with sulfur to form an ionic compound, potassium sulfide, K2S.
Complete the dot-and-cross diagram to show the electron arrangement and charges of the ions in
potassium sulfide.
.......
K
.......
S
.......
K
[3]
[Total: 3]
5
9
Ethene is an alkene which reacts with bromine as shown in the equation.
C2H4 + Br2 → C2H4Br2
Part of the energy profile diagram of this reaction is shown.
C2H4 + Br2
energy
progress of reaction
The reaction is exothermic.
Complete the energy profile diagram for this reaction.
Include:
•
the position of the products
•
an arrow to show the activation energy, labelled as A
•
an arrow to show the energy change for the reaction.
[3]
[Total: 3]
10 Calcium carbonate decomposes when heated.
calcium carbonate → calcium oxide + carbon dioxide
The decomposition of calcium carbonate is endothermic.
(a) State the meaning of the term endothermic.
...........................................................................................................................................
[1]
6
(b) The energy level diagram for the decomposition of calcium carbonate is shown.
CaO + CO2
energy
CaCO3
progress of reaction
Explain how the energy level diagram shows that this reaction is endothermic.
...........................................................................................................................................
...........................................................................................................................................
[1]
[Total: 2]
7
11
Nitrogen reacts with fluorine to form nitrogen trifluoride, NF3.
N≡N + 3 F–F ® 2 F–N–F
F
The chemical equation can be represented as shown.
Some bond energies are shown in the table.
bond
bond energy in kJ /mol
N≡N
945
F−F
160
N−F
300
(a) Calculate the energy change for the reaction between nitrogen and fluorine, using the following
steps:
·
energy taken in to break bonds
....................................... kJ
·
energy released when bonds are formed
....................................... kJ
·
energy change during the reaction.
....................................... kJ / mol
[3]
(b) Use your answer to (a) to deduce whether this reaction is endothermic or exothermic. Explain
your answer.
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...........................................................................................................................................
[1]
[Total: 4]
8
12 In a blast furnace carbon monoxide reduces iron(III) oxide to iron.
State the meaning of the term reduction.
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[1]
[Total: 1]
13 Ammonia is manufactured from nitrogen and hydrogen.
N2 + 3H2 ⇌ 2NH3
(a) Give the meaning of the symbol ⇌.
...........................................................................................................................................
[1]
(b) The nitrogen for this process is obtained from the air.
State the percentage of nitrogen in clean, dry air.
...........................................................................................................................................
[1]
[Total: 2]
14 Sulfuric acid is manufactured by an industrial process. Sulfur is obtained from sulfur-containing
metal ores.
The sulfur in the metal ore is converted to sulfur dioxide which is then oxidised to sulfur trioxide as
shown.
2SO2(g) + O2(g) ⇌ 2SO3(g)
The reaction that produces sulfur trioxide is an equilibrium. The forward reaction is exothermic.
(a) Describe two features of an equilibrium.
1 ........................................................................................................................................
2 ........................................................................................................................................
[2]
(b) State the effect, if any, on the position of equilibrium when the following changes are made.
Explain your answers.
temperature is increased ..................................................................................................
...........................................................................................................................................
pressure is increased .......................................................................................................
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[4]
[Total: 6]
9
15 Ethanoic acid is manufactured by the reaction of methanol with carbon monoxide.
An equilibrium mixture is produced.
CH3OH(g) + CO(g) ⇌ CH3COOH(g)
(a) State two characteristics of an equilibrium.
1 .......................................................................................................................................
2 .......................................................................................................................................
[2]
(b) The purpose of the industrial process is to produce a high yield of ethanoic acid at a high rate
of reaction.
The manufacture is carried out at a temperature of 300 °C.
The forward reaction is exothermic.
Use this information to state why the manufacture is not carried out at temperatures:
• below 300 °C
...........................................................................................................................................
• above 300 °C
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[2]
(c) Complete the table using only the words increases, decreases or no change.
effect on the rate of
the forward reaction
adding a catalyst
effect on the equilibrium
yield of CH3COOH(g)
no change
decreasing the pressure
[3]
(d) Suggest which of the following metals is a suitable catalyst for the reaction. Give a reason for
your answer.
aluminium calcium cobalt magnesium potassium
suitable catalyst ................................................................................................................
reason ..............................................................................................................................
[2]
[Total: 9]
10
16 Copper is a transition element. Sodium is an element in Group I of the Periodic Table.
Copper is harder than sodium.
(a) Give two other ways in which the physical properties of copper differ from the physical properties
of sodium.
1 ........................................................................................................................................
2 ........................................................................................................................................
[2]
(b) Give one use of copper.
...........................................................................................................................................
[1]
[Total: 3]
17 Aqueous chlorine reacts with aqueous sodium iodide.
Cl2 + 2NaI → 2NaCl + I2
Explain how this equation shows that chlorine is more reactive than iodine.
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[1]
[Total: 1]
18 One chemical property of transition elements is that they form coloured compounds.
(a) Give the colours of the following hydrated salts.
hydrated copper(II) sulfate ...............................................................................................
hydrated cobalt(II) chloride ...............................................................................................
[2]
(b) State two other chemical properties of transition elements.
1 ........................................................................................................................................
2 ........................................................................................................................................
[2]
[Total: 4]
11
19 Potassium reacts with water.
2K + 2H2O → 2KOH + H2
Describe two observations when potassium reacts with water.
1 ...............................................................................................................................................
2 ...............................................................................................................................................
[2]
[Total: 2]
20 Clean, dry air contains argon. Argon is unreactive.
(a) Explain, using ideas about electronic structure, why argon is unreactive.
...........................................................................................................................................
...........................................................................................................................................
[1]
(b) Give one use of argon.
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[1]
[Total: 2]
21 The symbols of the elements in Period 2 of the Periodic Table are shown.
Li
Be
B
C
N
O
F
Ne
For each of the following, give the symbol of an element from Period 2 which matches the description.
Each element may be used once, more than once or not at all.
Which element:
(a) combines with hydrogen to produce ammonia
...........................................................................................................................................
[1]
(b) makes up approximately 21% of clean, dry air
...........................................................................................................................................
[1]
(c) has atoms with only two electrons in the outer shell
...........................................................................................................................................
[1]
(d) has atoms with only seven protons
...........................................................................................................................................
[1]
12
(e) is a monoatomic gas
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(f)
[1]
is a soft metal stored in oil?
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[1]
[Total: 6]
22 Polluted air contains oxides of nitrogen.
(a) Give one source of oxides of nitrogen in the air.
...........................................................................................................................................
[1]
(b) State one adverse effect of oxides of nitrogen on health.
...........................................................................................................................................
[1]
[Total: 2]
23 The names of the elements of Period 2 of the Periodic Table are shown.
lithium
beryllium
boron
carbon
nitrogen
oxygen
fluorine
neon
Identify the element which is a product of photosynthesis.
..................................................................................................................................................
[1]
[Total: 1]
24 Two of the pollutants in air are oxides of nitrogen and lead compounds.
Name two other pollutants present in air.
State the source of each of these pollutants.
pollutant 1 ................................................................................................................................
source of pollutant 1 ................................................................................................................
pollutant 2 ................................................................................................................................
source of pollutant 2 ................................................................................................................
[4]
[Total: 4]
13
25 Describe how aqueous bromine can be used to distinguish between a saturated hydrocarbon and
an unsaturated hydrocarbon.
observations with saturated hydrocarbon ................................................................................
..................................................................................................................................................
observations with unsaturated hydrocarbon ............................................................................
..................................................................................................................................................
[2]
[Total: 2]
26 Ethanol and methanol are in the same homologous series.
Explain the meaning of the term homologous series.
..................................................................................................................................................
..................................................................................................................................................
[2]
[Total: 2]
27 The structures of four organic compounds, B, C, D and E are shown.
B
H
H
C
C
O
H
C
H
O
H
H
H
H
C
C
C
H
H
H
D
H
H
H
C
C
H
H
E
H
C
H
H
H
H
C
C
H
H
O
H
(a) State which compound, B, C, D or E, dissolves in water to form an acidic solution.
...........................................................................................................................................
[1]
(b) State which compound, B, C, D or E, is a saturated hydrocarbon.
...........................................................................................................................................
[1]
(c) State which compound, B, C, D or E, is an unreactive compound except in terms of burning.
...........................................................................................................................................
[1]
14
(d) State which compound, B, C, D or E, decolourises aqueous bromine.
...........................................................................................................................................
[1]
[Total: 4]
28 Compound G has the structure shown.
H
H
C
C
H
H
(a) Compound G can be obtained by cracking petroleum fractions.
Describe what is meant by the term cracking.
...........................................................................................................................................
...........................................................................................................................................
[2]
(b) Name the product of the reaction when compound G reacts with steam.
...........................................................................................................................................
[1]
(c) Many molecules of compound G can join together to form a compound with a very long chain.
Choose from the list the general name given to a compound that is formed by the addition of
many small units.
Draw a circle around the correct answer.
isomer
monomer
naphtha
polymer
[1]
[Total: 4]
15
29 Describe how simple distillation is used to separate water from an aqueous solution of sodium
sulfate.
In your answer, refer to:
•
the apparatus used,
•
changes in state,
•
differences in boiling points.
You may use a diagram.
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[5]
[Total: 5]
16
30 Carbon dioxide can be prepared in the laboratory using the apparatus shown below.
B
carbon
dioxide
A
hydrochloric acid
marble chips
(calcium carbonate)
State the names of the pieces of apparatus labelled A and B.
A ...............................................................................................................................................
B ...............................................................................................................................................
[2]
[Total: 2]