Question

Chemically bleaching powder is called:
(A) Calcium oxychloride
(B) Calcium chlorohypochlorite
(C) Calcium monooxygen chloride
(D) Calcium oxygen dichloride

Answer 1

Hint: The chemical formula of bleaching powder is$CaOC{{l}_{2}}$.. It is prepared by passing chlorine over slaked lime. Bleaching powder is used for disinfecting drinking water as the liberated chlorine kills the germs. Calcium has Valency as 2 , oxygen also has Valency as 2 and chlorine has Valency as 1.

Complete solution step by step:
Uses of bleaching powder:
- It is used for bleaching dirty clothes in the laundry. It acts as a bleaching agent for cotton and linen in the textile industry.
- It is used as an oxidizer in many industries as it is a strong oxidizing agent.
- It is used as a disinfectant which is used for disinfecting water to make potable water.
Method of preparation of bleaching powder:
Bleaching powder is synthesized by the action of chlorine gas($C{{l}_{2}}$) on dry slaked lime ($Ca{{(OH)}_{2}}$).
$Ca{{(OH)}_{2(s)}}+C{{l}_{2(g)}}\to CaOC{{l}_{2(s)}}+{{H}_{2}}{{O}_{(l)}}$
When bleaching powder($CaOC{{l}_{2}}$) reacts with dilute sulphuric acid(${{H}_{2}}S{{O}_{4}}$), it liberates chlorine gas ($C{{l}_{2}}$). This Chlorine gas is called Available chlorine.
Following is the reaction stating the same:
$CaOC{{l}_{2}}+{{H}_{2}}S{{O}_{4}}\to CaS{{O}_{4}}+C{{l}_{2}}+{{H}_{2}}O$
The valency of Chlorine atom increases to 0 in this reaction. Hence, Chlorine undergoes Oxidation in this reaction.
As the chemical formula of bleaching powder is$CaOC{{l}_{2}}$

So the correct option is (A) Calcium oxychloride.

Note: Bleaching powder is also called chlorine powder, chloride of lime or chlorinated lime. The other chemical name is Calcium hypochlorite. It is a white powder with odour of chlorine. It is a strong Oxidizing agent. Dilute acids react quickly with bleaching powder to release chlorine gas. - It is used for bleaching dirty clothes in the laundry. It acts as a bleaching agent for cotton and linen in the textile industry.