1
1
What are the products at the electrodes when dilute sulfuric acid is electrolysed using inert
electrodes?
anode
cathode
A
hydrogen
oxygen
B
oxygen
hydrogen
C
sulfur
oxygen
D
sulfur dioxide
hydrogen
[1]
[Total: 1]
2
Electricity is passed separately through concentrated hydrochloric acid, concentrated aqueous
sodium chloride and dilute sulfuric acid.
In which rows are the electrolysis products correctly named?
A
cathode product
anode product
1
concentrated
hydrochloric acid
hydrogen
chlorine
2
concentrated
aqueous sodium chloride
sodium
chlorine
3
dilute sulfuric acid
hydrogen
oxygen
1, 2 and 3
B
1 and 2 only
C
1 and 3 only
D
2 and 3 only
[1]
[Total: 1]
3
Which reactions could take place at the anode during electrolysis?
A
−
2H2O(I) + O2(g) + 4e
1
4OH (aq)
2
2Cl (aq)
3
Cu (aq) + 2e
4
2H (aq) + 2e
−
Cl 2(g) + 2e
2+
1 and 2
+
−
−
B
−
−
Cu(s)
H2(g)
1 and 4
C
2 and 4
D
3 and 4
[1]
2
[Total: 1]
4
The diagram shows a simple cell.
voltmeter
V
copper electrode
zinc electrode
electrolyte
Which statement about the process occurring when the cell is in operation is correct?
A
Cu
B
Electrons travel through the solution.
C
The reaction Zn
D
The zinc electrode increases in mass.
2+
ions are formed in solution.
2+
Zn
−
+ 2e occurs.
[1]
[Total: 1]
3
5
When concentrated hydrochloric acid is electrolysed, gases P and Q are formed.
P
Q
concentrated
hydrochloric acid
platinum
electrodes
–
+
What are P and Q?
P
Q
A
chlorine
hydrogen
B
chlorine
oxygen
C
hydrogen
chlorine
D
hydrogen
oxygen
[1]
[Total: 1]
4
6
The diagram shows the apparatus used for the electrolysis of molten sodium bromide.
R
+
–
S
U
T
What does the term electrolysis mean?
..................................................................................................................................................
..................................................................................................................................................
[1]
[Total: 1]
7
A student electrolyses aqueous copper(II) sulfate using the apparatus shown.
power supply
+
–
carbon electrodes
aqueous
copper(II) sulfate
Oxygen gas forms at the positive electrode (anode).
(a) Describe what the student observes at the negative electrode.
...........................................................................................................................................
[1]
(b) Give two other observations which the student makes during the electrolysis.
1.........................................................................................................................................
2.........................................................................................................................................
[2]
[Total: 3]
5
8
The table gives information about the products of the electrolysis of two electrolytes. Platinum
electrodes are used in each case.
(a) Give two reasons why platinum is suitable to use as an electrode.
1.........................................................................................................................................
2.........................................................................................................................................
[2]
(b) Complete the table.
electrolyte
observation
at the anode (+)
name of product
at the anode (+)
concentrated
aqueous
potassium chloride
aqueous
copper(II) sulfate
observation
at the cathode (−)
name of product
at the cathode (−)
bubbles of
colourless gas
bubbles of
colourless gas
[6]
[Total: 8]
9
Magnesium is manufactured by the electrolysis of molten magnesium chloride.
The negative electrode is made of iron.
Suggest a non-metal which could be used for the positive electrode.
Give a reason for your answer.
..................................................................................................................................................
..................................................................................................................................................
[2]
[Total: 2]
6
10 A student electrolyses aqueous copper(II) sulfate using the apparatus shown.
power supply
+
–
carbon electrodes
aqueous
copper(II) sulfate
Oxygen gas forms at the positive electrode (anode).
Write an ionic half-equation for the reaction at the negative electrode (cathode).
Include state symbols.
..................................................................................................................................................
[3]
[Total: 3]
11
12