Page 1 - CBW

SAI International School

Competency Based Worksheet
Subject – Chemistry

Chapter – Chemical effect of electric current

Class- VIII

Q. No. Questions

1. The process of depositing a layer of metal on another object using electricity is called
A) Rusting
B) Electroplating
C) Electrolysis
D) Galvanization
2. In electroplating, the object to be electroplated is connected to the:
A) Positive terminal
B) Negative terminal
C) Both terminals
D) None of the terminal
3. What gas is formed at the cathode during the electrolysis of water
A) Oxygen
B) Nitrogen
C) Hydrogen
D) Carbon dioxide
4. The application of electroplating can be found in:
A) Making artificial rain
B) Water purification
C) Gold coating on jewellery
D) Cleaning utensils
5. Electrolysis of water produces Hydrogen and oxygen in the ratio:
A) 1:2
B) 1:3
C)2:1
D)2:3
Choose the correct option for the following: (For questions- 6,7, 8)
a) If both Assertion and Reason are correct and Reason is the correct explanation of
Assertion.
b) If both Assertion and Reason are correct, but Reason is not the correct explanation of
Assertion.
c) If Assertion is correct but Reason is incorrect.
d) If assertion is incorrect but Reason is correct.
e) If Assertion and Reason both are incorrect.
6. Assertion (A): Lemon juice can conduct electricity.
Reason (R): Lemon juice is a strong acid that releases ions in water.
7. Assertion (A): Electroplating is a chemical effect of electric current.
Reason (R): Electroplating involves heating of a conducting wire.