JEE MAIN - Chemistry (2002 - No. 22)
How do we differentiate between Fe3+ and Cr3+ in group III?
by taking excess of NH4OH solution
by increasing $$NH_4^+$$ ion concentration
by decreasing OH- ion concentration
both (b) and (c)
Explicação
FeCl3 + 3NH4OH $$ \to $$ Fe(OH)3 ↓(reddish brown) + 3NH4Cl
CrCl3 + 3NH4OH $$ \to $$ Cr(OH)3 (Bluish green) + 3NH4Cl
CrCl3 + 3NH4OH $$ \to $$ Cr(OH)3 (Bluish green) + 3NH4Cl