When hydrogen chloride gas is prepared 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

Q. When hydrogen chloride gas is prepared 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

1. absorb the evolved gas
2. moisten the gas
3. absorb moisture from the gas
4. absorb Cl– ions from the evolved gas

Answer: absorb moisture from the gas