Hydrogen chloride gas is prepared in the laboratory using concentrated sulphuric acid

Compounds (10)

Hydrogen chloride gas is prepared in the laboratory using concentrated sulphuric acid and sodium chloride. Answer the questions that follow based on this reaction:

  1. Give the balanced chemical equation for the reaction with suitable condition(s) if any.
  2. Why is concentrated sulphuric acid used instead of concentrated nitric acid?
  3. How is the gas collected?
  4. Name the drying agent not used for drying the gas.

Answer

(i) NaCl + (conc.) H2SO4 → NaHSO4 + HCl (Reaction at < 200ºC)

(ii) Concentrated H2SO4 is non-volatile / least volatile / less volatile / has high boiling point and hence can displace the more volatile HCl gas from the salt

Concentrated nitric acid is a volatile acid / low boiling point and will displace out itself along with HCl gas

(iii) Upward displacement of air/ downward delivery / downward delivery of gas

(iv) Quick lime / calcium oxide / phosphorus pentoxide

  • Exam Year: 2020