Question

Question 03.
During the preparation of hydrogen chloride gas on a humid day, the gas is usually passed through the guard tube containing calcium chloride. The role of calcium chloride taken in the guard tube is to
(a) absorb the evolved gas
(b) moisten the gas
(c) absorb moisture from the gas
(d) absorb ${\text{Cl}}^{-}$ ions from the evolved gas

Answer 1

Due to the presence of humidity, hydrogen chloride gas may be lost as hydrochloric acid. To get anhydrous hydrogen chloride, ${\text{CaCl}}_2$ is taken in a guard tube because it is a dehydrating agent and absorbs moisture.