Question

Which will not be precipitated after addition of
Ammonium carbonate in presence of NH4CI :-

(1) Mg (2) Ba

(3) Ca (4) Sr

Answer 1

Solution:
When (NH4)2CO3 is added to salt solution containing NH4Cl and NH4OH, the carbonates of Ba2+, Sr2+ and Ca2+ are precipitated:
BaCl2+(NH4)2CO3 → BaCO3↓+ 2NH4Cl
SrCl2+(NH4)2CO3 → SrCO3↓+ 2NH4Cl
CaCl2+(NH4)2CO3 → CaCO3↓+ 2NH4Cl
Then answer (1) - Mg