Compound A reacts with NH4Cl and forms a compound B . Compound B reacts with H2O and excess of CO2 to form compound C which on passing through or reaction with saturated NaCl solution forms sodium hydrogen carbonate. Compound A . B and C , are respectively.
(A)CaCl2,NH3,NH4HCO3
(B)CaCl2,NH4+,(NH4)2CO3
(C)Ca(OH)2,NH3,NH4HCO3✓ Correct
(D)Ca(OH)2,NH4+,(NH4)2CO3
Answer: (C)
Solution
Warming slaked lime with ammonium chloride liberates ammonia, Ca(OH)X2+2NHX4ClCaClX2+2NHX3+2HX2O, so the first substance is calcium hydroxide and the gas obtained is ammonia. This ammonia, in water with excess carbon dioxide, forms ammonium hydrogen carbonate, NHX3+HX2O+COX2NHX4HCOX3. Passing this through saturated sodium chloride solution throws down the sparingly soluble sodium hydrogen carbonate, NHX4HCOX3+NaClNaHCOX3+NHX4Cl. The three compounds are calcium hydroxide, ammonia and ammonium hydrogen carbonate.
JEE Main · 2023 · 25 Jan 2023 · Shift 1 · Single correct option