Question

Chlorine and oxygen are negatively charged. So, during the chlor-alkali process, how do sodium hydroxide and chlorine (by-products) combine to form sodium hypochlorite?

Answer 1

1. In chlor-alkali process, the molecules of NaOH and Cl₂ are formed by the process of electrolysis.

2. In electrolysis, there are two simultaneous reactions taking place at anode and cathode induced by electricity.

3. They are as follows:

Anode: 2 Cl^-(aq) $\to$Cl_​2 + 2e^- ...(1)

Cathode: 2 Na⁺ +2 e^- ​$\to$ 2 Na
2 Na +2 H₂O ​$\to$ 2 NaOH + H₂ ..(2)

When reaction (1) and (2) are summed up give Chlor-Alkali process which is:

2 NaCl + 2 H₂O ​$\to$ 2 NaOH + Cl₂ + H₂