Question

(a) What is the common name of the compound $CaOC{l}_2$ ?

(b) Name the raw material used for the preparation of plaster of Paris.

(c) Which property of plaster of plaster of Paris is utilised in making casts for broken limbs in hospitals ?

(d) Explain why chlorine is used for sterilising drinking water supply.

Answer 1

(a) bleaching powder

(b) gypsum

(c) it sets into a hard mass in about 30 mins thus ensuring safety and giving bone enough time to recover.

(d) As a halogen, chlorine is a highly efficient disinfectant, and is added to public watersupplies to kill disease-causing pathogens, such as bacteria, viruses, and protozoans, that commonly grow in water supply reservoirs, on the walls of watermains and in storage tanks.