Question

In the synthesis of sodium carbonate, the recovery of ammonia is done by treating NH₄Cl with Ca(OH)₂. The by-product obtained in this process is ______.

विकल्प

• CaCl₂

• NaCl

• NaOH

• NaHCO₃

Answer 1

In the synthesis of sodium carbonate, the recovery of ammonia is done by treating NH₄Cl with Ca(OH)₂. The by-product obtained in this process is CaCl₂.

Explanation:

Sodium carbonate is synthesised by Solvay or ammonia soda process. The reactions involved are

\[\ce{NH3 + H2O + CO2 -> \underset{Ammonium bicarbonate}{NH4HCO3}}\]

\[\ce{NaCl + NH4HCO3 -> \underset{Sodium bicarbonate}{NaHCO3} ↓ + NH4Cl}\]

\[\ce{2NaHCO3 ->[Δ] \underset{Sodium carbonate}{Na2CO3} + H2O +CO2 }\]

NH₃ is recovered from NH₄HCO₃ and NH₄Cl formed during the reaction.

\[\ce{NH4HCO3 ->[Heat] NH3 + H2O + CO2}\]

\[\ce{\underset{Ammonium chloride}{2NH4Cl} + Ca(OH)2 -> \underset{Ammonia}{2NH3} + \underset{Calcium chloride}{CaCl2} + H2O}\]