Bleaching Powder

Question 1 A white powdery substance having strong smell of chlorine is used for disinfecting drinking water supply at water works. Identify the substance?

Question 2 Write the chemical name and formula of bleaching powder?

Question 3 How is bleaching powder prepared. Give the chemical equation?

Question 4 State uses of bleaching powder?

Question 5 List few properties of bleaching powder?

📋 Contents

1 Bleaching Powder
2 Preparation of Bleaching Powder
3 Uses of Bleaching Powder

It is calcium oxychloride. It is also called as the chloride of lime. The chemical formula of bleaching powder is CaOCl₂

Preparation of Bleaching Powder

It is prepared by passing chlorine gas over dry slaked lime.

Properties of Bleaching Powder

(1) It is a white powder which gives strong smell of chlorine.

(2) It is soluble in cold water.

(3) It reacts with dilute acids to produce chlorine. When bleaching powder is treated with an excess of a dilute, all the chlorine present in it is liberated. For example, when bleaching powder is treated with an excess of dilute sulphuric acid, all the chlorine present in it liberated.

(5) Here, the chlorine produced by the action of dilute acid on bleaching powder acts as a bleaching agent. Thus, the real bleaching agent present in bleaching powder is chlorine.

Uses of Bleaching Powder

(1) It is used for bleaching cotton and linen in textile industry.

(2) It is used for bleaching wood pulp in paper industry.

(3) It is used for disinfecting drinking water supply.

(4) It is used in the manufacture of chloroform.

(5) It is used to make wool unshrinkable.

(6) It is used as an oxidising agent in many chemical industries.