A compound (A) is used in preparation of washing soda to recover ammonia in Solvay's process. When C — s Block Elements Chemistry Question
Question
A compound (A) is used in preparation of washing soda to recover ammonia in Solvay's process. When CO2 is bubbled through an aqueous solution of (A), the solution turns milky. It is used in white washing due to disinfectant nature. What is the chemical formula of A?
💡 Solution & Explanation
Step 1: In the Solvay process, ammonia is recovered by heating ammonium chloride with calcium hydroxide (slaked lime): 2NH4Cl + Ca(OH)2 -> CaCl2 + 2NH3 + 2H2O. Step 2: When carbon dioxide is bubbled through an aqueous solution of Ca(OH)2 (lime water), it forms a white precipitate of calcium carbonate (CaCO3), turning the solution milky: Ca(OH)2 + CO2 -> CaCO3 + H2O. Step 3: Calcium hydroxide (Ca(OH)2) is also widely used for whitewashing due to its disinfectant properties. Thus, compound (A) is Ca(OH)2, corresponding to option (c).