Question

Which among the following sets of compounds is used as raw material for the preparation of sodium carbonate by Solvay process?

विकल्प

• NaOH, HCl, CO₂

• NH₄Cl, H₂O, NaCl

• NaCl, NH₃, Ca(OH)₂

• NaCl, CaCO₃, H₂SO₄

Answer 1

NaCl, NH₃, Ca(OH)₂ 

Explanation:

For the preparation of sodium carbonate by Solvay process, raw materials used are NaCl, NH₃ and Ca(OH)₂ (for CO₂).

The process involves the following reactions.

\[\ce{NH3 + H2O + CO2 -> NH4NO3}\]

\[\ce{CaCO3 ->[\Delta] CaO + CO2}\]

\[\ce{NaCl + NH4HCO3 -> NaHCO3 + NH4Cl}\]

\[\ce{CaO + H2O -> Ca(OH)2}\]

\[\ce{2NH4Cl + Ca(OH)2 -> CaCl2 + 2NH3 + 2H2O}\]

\[\ce{2NaHCO3 ->[\Delta] Na2CO3 + H2O + CO2}\]

Most of the NH₃ can be recovered in the process.