Question

Colourless solid (A) $\stackrel{△}{⟶}$ (B) (gas) + (C) (gas). Aqueous solutions of (A) and (B) turn blue litmus red, while that of (C) turns red litmus blue. Aqueous solutions of (A) and (B) also give white precipitate with $AgN{O}_3$ solution, which is soluble in aqueous solution of (C). (A), (B) and (C) in correct order are :

• A. $N{H}_{4}Cl$, $N{H}_3$ and $HCl$
• B. $N{H}_{4}Cl$, $HCl$ and $N{H}_3$
• C. $HCl$, $N{H}_{4}Cl$ and $N{H}_3$
• D. $N{H}_3$, $HCl$ and $N{H}_{4}Cl$

Answer 1

The correct option is B $N{H}_{4}Cl$, $HCl$ and $N{H}_3$

Ammonium chloride solid (A) on heating gives HCl gas (B) and ammonia gas (C):

$\underset{A}{N{H}_{4}Cl}\stackrel{\Delta }{⟶}\underset{B}{HCl}\uparrow +\underset{C}{N{H}_3}\uparrow$

Ammonium chloride and hydrogen chloride are acidic in nature and they turn blue litmus red. Ammonia is basic in nature and it turns red litmus blue.
Ammonium chloride and hydrogen chloride contains chloride ions which reacts with silver ions present in silver nitrate to form white precipitate of silver chloride which is soluble in excess of ammonia.

$A{g}^{+}+C{l}^{-}\rightleftharpoons AgCl\downarrow$

$AgCl+2N{H}_{4}OH\to \underset{\text{soluble complex}}{Ag(N{H}_3{)}_{2}Cl}+2H_{2}O$