During the preparation of hydrogen chloride gas on a humid day, the gas is usually passed through the guard tube containing calcium chloride. What is the role of calcium chloride?
absorb the evolved gas
moisten the gas
absorb moisture from the gas
absorb Cl⁻ ions from the evolved gas
Steps: Calcium chloride is a desiccant (drying agent). It removes moisture from gases. So it absorbs moisture from the HCl gas to give dry HCl.