Question

In one of the industrial processes used for manufacture of sodium hydroxide, a gas X is formed as by product. The gas X reacts with lime water to give a compound Y which is used as a bleaching agent in chemical industry. Identify X and Y giving the chemical equations of the reactions involved​.

Answer 1

In chlor-alkali process, chlorine and hydrogen gases are formed as by-products along with sodium hydroxide. ​

$2\text{NaCl(aq) + 2}{\text{H}}_2\text{O(l)}\to 2{\text{NaOH(aq) + Cl}}_2{\text{(g) + H}}_2\text{(g)}$

Chlorine gas produces bleaching power when it reacts with lime water ${\text{(Ca(OH)}}_2)$. Bleaching powder is used as a bleaching agent in chemical industries.​

${\text{Ca(OH)}}_2\text{(s)}+{\text{Cl}}_2\text{(g)}\to {\text{CaOCl}}_2\text{(s)}+{\text{H}}_2\text{O(l)}$
​
Therefore, X is chlorine gas, and Y is bleaching powder.