Essential Chemistry for IGCSE - Electricity And Chemistry (Section 5)
1
Which of the following factors can affect the products of electrolysis? (Select all that apply)
Answer
A
B
2
During the electrolysis of aluminum oxide, where does the reduction of aluminum ions take place?
Answer
(B)
The cathode
3
Which statement best describes the reaction at the anode during the electrolysis of aluminum oxide?
Answer
(B)
Oxygen is formed.
4
What will be the product at the anode during the electrolysis of copper(II) sulfate solution (CuSO4) using inert electrodes?
Answer
(B)
Oxygen
5
Which of the following correctly identifies the products formed during the electrolysis of dilute sulfuric acid (H2SO4) using inert electrodes? (Select all that apply)
Answer
A
B
6
Which of the following statements is true for electroplating?
Answer
(D)
All of the above.
7
What is a common issue with thin wires in high-voltage power lines?
Answer
(B)
They have a high resistance.
8
Why is aluminium more suitable than iron to transmit electricity?
Answer
(C)
Both A and B.
9
During the electrolysis of copper sulfate solution with copper electrodes, what change happens at the anode?
Answer
(B)
Copper dissolves.
10
What is the name of the compound used to extract aluminum from aluminium oxide?
Answer
(B)
Cryolite
11
In the extraction of aluminium, what is the primary function of the carbon anodes?
Answer
(C)
To allow for the release of oxygen
12
Why is aluminum considered a good conductor of electricity?
Answer
(B)
It has a low resistance to the flow of electricity.
13
In the electrolysis of a solution of silver nitrate (AgNO3) using inert electrodes, silver is deposited at which electrode?
Answer
(B)
Cathode
14
Which of the following represents the correct half-reaction at the anode during the electrolysis of copper sulfate solution using copper electrodes?
Answer
(B)
Cu → Cu2+ + 2e-
15
During the electrolysis of a dilute aqueous solution, at which electrode will oxygen gas be formed?
Answer
(A)
Anode
16
What are the two main ions in the electrolytic solution of copper sulfate (CuSO4) in the electrolysis of the substance?
Answer
(A)
Copper (Cu2+) and sulfate (SO42-)
17
What is the function of cryolite in the electrolytic cell used for aluminum extraction?
Answer
(B)
To lower the melting point of the aluminum oxide.
18
Which are the main materials used to make a high-voltage power cable?
Answer
A
C
19
In the extraction of aluminum, what is the purpose of adding cryolite to the aluminum oxide?
Answer
(D)
Both B and C.
20
Which of the following is/are true regarding electrolysis? (Select all that apply)
Answer
A
B
C
21
In electroplating, why must the object to be plated be meticulously cleaned before use?
Answer
(C)
To ensure the plating adheres evenly and properly.
22
When electroplating with silver, which of the following would be the best choice for the electrolyte?
Answer
(D)
Silver nitrate solution
23
In high-voltage power lines, why are steel-cored aluminum cables used?
Answer
(A)
Steel provides strength to prevent sagging, while aluminum is a good conductor.
24
In the electrolysis of water, the volume ratio of hydrogen gas produced to oxygen gas produced is:
Answer
(B)
2:1
25
Which material is commonly used to make the anode in the electrolysis of aluminum oxide?
Answer
(C)
Graphite
26
When electroplating, the object you want to coat should be connected to which terminal?
Answer
(B)
Negative
27
What type of reaction takes place at the anode during electrolysis?
Answer
(B)
Oxidation
28
In the process of electroplating, what is the primary role of the electrolyte?
Answer
(A)
To provide the metal ions that will be deposited.
29
What is the purpose of using a silver anode in electroplating?
Answer
(B)
To supply silver ions to the solution.
30
Which of the following statements is true regarding the electrical conductivity of copper wires compared to aluminum wires of the same thickness?
Answer
(A)
Copper wires have a lower resistance, so they have better conductivity.
31
If a student uses inert electrodes to electrolyze a solution of copper (II) sulfate, which substance will be produced at the anode?
Answer
(C)
Oxygen
32
Which of the following factors affect the products formed during electrolysis? (Select all that apply)
Answer
A
B
C
33
Which of the following is the correct half-equation for the reaction at the cathode during the electrolysis of molten NaCl?
Answer
(B)
Na+ + e- -> Na
34
Which of the following statements describes the process of electrolysis?
Answer
(A)
The decomposition of a substance by passing electricity through it.
35
Which of the following metals is commonly used as an anode in electroplating?
Answer
(C)
Silver
36
What happens to the impurities in bauxite during its purification?
Answer
(C)
They are filtered off.
37
What type of energy conversion occurs in an electrolytic cell?
Answer
(B)
Electrical to chemical
38
During the electrolysis of copper sulfate solution using inert electrodes, which product is formed at the anode?
Answer
(B)
Oxygen
39
What is the key difference between a voltaic cell and an electrolytic cell?
Answer
(B)
Voltaic cells are spontaneous, while electrolytic cells are non-spontaneous.
40
During the electrolysis of brine, the products formed are used in the manufacture of which of the following products?
Answer
(B)
Sodium hydroxide
41
Which of the following is a practical application of electroplating? (Select all that apply)
Answer
A
B
42
What is the purpose of refining copper by electrolysis?
Answer
(B)
To remove impurities
43
What is the purpose of the siphon tube in aluminium extraction?
Answer
(A)
To remove the molten aluminium.
44
What will be produced at the anode during the electrolysis of a concentrated solution of sodium chloride?
Answer
(B)
Chlorine
45
Which of the following is essential for electrolysis to occur?
Answer
(A)
A closed circuit with a power source.
46
In an electrolytic cell, which electrode is connected to the negative terminal of the power supply?
Answer
(B)
Cathode
47
In the electroplating of a metal object, where does the reduction of the metal ions occur?
Answer
(B)
Cathode
48
What materials are good conductors of electricity?
Answer
A
B
D
49
Which of the following are examples of conductors?
Answer
B
C
50
In the context of aluminum extraction, what is the function of the cathode?
