One litre of 1M solution of CoCl3.4NH3 require ‘V’ litres of 2M AgNO3 solution to precipitate all the chloride ions. Value of ‘V’ is

Modern formula of CoCl3.4NH3 is CoNH34Cl2Cl;  CoNH34Cl2Cl ⇌CoNH34Cl2++Cl-; Valency of the complex is one; Valency of silver nitrate is one; V1N1=V2N2; 1 1M = V 2M; VAgNO3= 0.5 litre;