Question

Predict the products of electrolysis of the following substances at anode and cathode using suitable
chemical equations.
(a) Aqueous NaCl (b) H2SO, solution
​

Answer 1

12th/Chemistry

Electrochemistry

Answer :

Electrolysis is the process of decomposition of an electrolyte by passing electricity through its aqueous solution or molten state.

➤ Aqueous NaCl

★ Product at cathode : H₂ gas

• H₂O + e‾ ➠ 1/2H₂ + OH‾ [Reduction]

★ Product at anode : Cl₂ gas

• Cl‾ ➠ 1/2Cl₂ + e‾ [Oxidation]

➤ Dil. H₂SO₄

★ Product at cathode : H₂ gas

• H$^+$ + e‾ ➠ 1/2H₂ [Reduction]

★ Product at anode : O₂ gas

• 2H₂O ➠ O₂ + 4H$^+$ [Oxidation]

Cheers!

Answer 2

Answer:As follow in the explanation

Explanation:

a) When aqueous NaCl is electrolysed, we get H2 gas at the cathode and Cl2 gas at the anode.

NaCl solution contains 4 ions – Na+

, Cl-

, H+ and OHCathode reaction: H+ + e- → ½ H2

Anode reaction: Cl- → ½ Cl2 + eNaOH is formed in the solution.

b) H2SO4 solution contains H+

, OH- and SO4

2-

ions. On electrolysis, the following reactions occur at the

electrodes.

Cathode reaction: H+ + e- → ½ H2

Anode reaction: 2H2O → O2 + 4H+ + 4e –

(for concentrated solution)

2SO4

2– →S2O8

2 – + 2e –

(for dilute solution)

(peroxodisulphate ion