class 8
CHEMICAL EFFECTS OF ELECTRIC CURRENT

I Fill in the blanks:-

1. A Compound formed by ions is called ________ .

2. The electrode connected to the negative terminal is _________ .

3. Distilled water does not conduct _______.

4. Electroplating is an important use of _______ .

II Choose the correct option:-

1 A liquid metal that conducts electricity :-

(a) Sodium (b) Mercury (c) Lead (d) Gold

2. An atom or a radical that becomes charged is called :-

(a) Radical (b) ion (c) electrode (e) none

3. Metals are extracted from their ores by the process of :-

(a) electroplating (b) electrolysis (c) both (d) none

III Name the following:-

1. An atom that loses an electron

2. Cell used in electrolysis

3. A liquid or a moist paste that has ions in it

IV Define the following:-

1. Electrolysis.

2. Electroplating.

3. Electrolyte.

4. Electrode.

V Draw the following diagrams and label it.

1. Electroplating steel spoons with silver.

2. Flow of ions in an electrolyte.

3. Electrodes.

VI Give reasons for the following:-

1. An acid or ionic salt added to water during the electrolysis of water.

2. Water taps are coated with nickel or chromium.