Question

(a) What is the difference between washing soda and baking soda?
​(b) Write the chemical formula for bleaching powder. How is bleaching powder prepared? For what purpose is it used in paper factories?

Answer 1

(a) Washing soda: Chemical formula of washing soda is ${{\mathrm{Na}}_2\mathrm{CO}}_3.10{\mathrm{H}}_2\mathrm{O}$. Washing soda used as a cleansing agent in domestic household purposes.

Baking Soda: Chemical formula of baking soda is NaHCO₃. Baking soda is used as an antacid to remove acidity in the stomach.

(b) The chemical formula of bleaching powder is CaOCl₂.
Bleaching powder is prepared by passing chlorine gas over dry calcium hydroxide.
$\mathrm{Ca}(\mathrm{OH}{)}_2+{\mathrm{Cl}}_2\to \underset{\mathrm{bleaching}\mathrm{powder}}{{\mathrm{CaOCl}}_2}+{\mathrm{H}}_2\mathrm{O}$

Bleaching powder is used in paper factories for bleaching wood pulp, as bleaching powder is a strong oxidizing agent.