Question

Naina was preparing a compound in the laboratory. She added compound ‘A’ to (CaOH)₂ solution. As a result of this, a compound ‘B’ was obtained which had a pungent smell. On adding Nessler’s reagent to the compound ‘B’, a brown precipitate of compound ‘C’ was obtained.

Write the chemical reactions involved and identify ‘A’, ‘B’ and ‘C’.

Answer 1

i. When ammonium chloride is mixed with (CaOH)₂ solution, ammonia is formed which has a pungent odour.

ii. Ammonia react with Nessler’ s reagent (an alkaline solution of K₂Hgl₄) to form a brown precipitate (Millon’ s base).

A: NH₄Cl (Ammonium chloride)

B: NH₃ (Ammonia) 

C: H₂N - Hg - O - Hg - I (Millon's base)