Question

Concentrated hydrochloric acid when kept in open air sometimes produces a cloud of white fumes. This is due to :

• A. Strong affinity of HCl gas for moisture in air results in forming of droplets of liquid solution which appears like a cloudy smoke.
• B. Strong affinity for water, conc. HCl pulls moisture of air towards self. The moisture forms droplets of water and hence the cloud.
• C. Conc. HCl emits strongly smelling HCl gas all the time.
• D. Oxygen in air reacts with emitted HCl gas to form a cloud of chlorine gas.

Answer 1

Answer: (D)

Oxygen in air reacts with emitted HCl gas to form a cloud of chlorine gas.

Answer 2

4HCI + O2 $\rightarrow$ 2CI2 + 2H2O white fumes cloud