Fill in the blanks

(a) The object to be electroplated is taken as ____________ electrode.

(b) One of the most common applications of chemical effect of electric current is ______________.

(c) Small amount of a mineral salt present naturally in water makes it a______________ of electricity.

(d) Electroplating of ______________ is done on objects like water taps and cycle bell to give them a shiny appearance.

(a)

Cathode or negative electrode

In the process of electroplating positive ions are released from the positive electrode or anode into the solution. Now they get attracted by the negative electrode or cathode and get drawn towards it. Therefore, the object to be electroplated is taken as cathode.

Example:

Deposition of copper coating from copper sulphate solution over the copper plate.

This can also be verified by connecting a carbon rod instead of copper at the cathode. on performing electroplating, we get copper coating on the carbon rod.

(b)

Electroplating

Electroplating is the most common use of chemical effect of current.

It is the process of depositing a layer of any desired metal on another material by means of electricity.

(c)

Good conductor

When salt is dissolved in distilled water, we obtain a salt solution which is a good conductor of electricity

(d)

Chromium

Chromium is used for electroplating of such objects because:

1. Applying chromium coating on the metal gives shiny appearance to the object.

2. Chromium coating on the object prevents it from rusting and act as a protective shield.

3. Chromium increase hardness of surface of object.