Question

Explain which type of change occurs when water is electrolyzed?

Answer 1

Electrolysis of water:

1. Electrolysis of water is a phenomenon in which Hydrogen and Oxygen get separated with the help of electricity like

$\underset{\mathrm{Water}}{2{\mathrm{H}}_2\mathrm{O}}\left(\mathrm{aq}\right)\stackrel{\mathrm{electricity}}{\to }\underset{\mathrm{Hydrogen}\mathrm{gas}}{2{\mathrm{H}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Oxygen}\mathrm{gas}}{{\mathrm{O}}_2\left(\mathrm{g}\right)}$

2. It is an irreversible change.

3. It is based on the principle when two inert electrodes are placed in the water and DC current is applied to both terminals, then at the cathode Hydrogen is deposited and at the anode, Oxygen is deposited.

Factors affecting electrolysis of water:

• Ions mobility to reach the electrodes.
• Activation energy
• A number of positive ions and negative ions are available.

Changes occur during electrolysis of water:

1. Three types of changes take place when water is electrolyzed.
2. These changes are irreversible change, physical change, and chemical change.
3. The state change of water into gas is a physical change.
4. It evolves Hydrogen gas and Oxygen gas so is a chemical change.

Hence, three basic changes occur when water is electrolyzed