In Nessler's reagent for the detection of ammonia the active species is

Question

In Nessler's reagent for the detection of ammonia the active species is (A) Hg 2 Cl 2 (B) Hg 2+ (C)  Hg 2 l2- (D) Hgl 4 2-

Tardigrade Admin · Accepted Answer

Following is the sequence of preparation of Nesseler's reagent.

H g C l_{2} + 2 K l \to 2 K Cl + H g l_{2}

H g l_{2} + 2 K l \to K_{2} H g l_{4}

Alkaline solution of this complex

K_{2} H g l_{4}

is called Nessler's reagent.
Formation of Million's base :

K_{2} H g I_{4} [] 2 K I + H g I_{2}

Q. In Nessler's reagent for the detection of ammonia the active species is