CHEMICAL EFFECTS OF ELECTRIC CURRENT CLASS VIII

I. Write answer for the following as directly :

1. What is LED ?

2. Name a gas which burns with a pop sound.

3. Which electrode is connected to the negative terminal of a cell ?

4. Name the ions which are positively charged.

5. Name a device which is used for the electrolysis of water

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II Answer the following in 2 or 3 lines :

1. Define the following :

a) Electrolyte b) Cathode c) Anode d) Jons

2. What is electroplating ?

3. Draw a neat diagram of electrolytic cell and label it

4. Identify the following as electrolytes and non electrolytes :

a) dil HNo3 b) Benzene c) Petrol d) Zinc Chloride solution e) a solution of NaOH g) Ether h) Alcohol i) Common salt solution

5. State three uses of electrolysis.

III Define the following in detail :

1. Describe an experiment to show chemical effect of electric current.

2. Describe an experiment for the electroplating of an iron object with copper.