Question

Name the gases evolved at anode and cathode on electrolysis of water

Answer 1

Answer:

At the cathode, hydrogen gas is evolved and at the annode, oxygen gas is evolved.

Answer 2

Hydrogen is evolved at the cathode and oxygen at the anode:

• At the cathode for the formation of hydrogen gas, $H^{+}$ takes up two electrons. Once, two moles   $H^{+}$ are formed it leads to the formation of one mole of hydrogen gas.
• The $OH^{-}$ present at the anode releases two electrons and then forms water and oxygen gas. Two moles of $OH^{-}$ lead to the formation of 0.5 moles of oxygen gas.