KVPY SX SB Exam 2016 Question Paper

M.wt = 59 +12 + 14 × 4 + 35.5 × 3 = 233.5
$\mathit{C}\mathit{o}{\mathit{H}}_{12}{\mathit{N}}_4\mathit{C}{\mathit{l}}_3\stackrel{{\mathrm{AgNO}}_3}{\to }1.435\mathit{g}\mathrm{AgCl}$
$\frac{2.33}{233.5}\mathit{g}=0.01\mathrm{mole}$ (0.01 mole)
(i) 0.01 mole molecule produce 0.01 mole AgCl
∴ one replaceable ${\mathrm{Cl}}^{-}$ ion
so formula of complex is $\left[\mathit{C}\mathit{O}{\left(\mathit{N}{\mathit{H}}_3\right)}_4\mathit{C}{\mathit{l}}_2\right]\mathit{C}\mathit{l}$
(ii) Oxidation no. of Co is +3 so primary valency is 3.
(iii) Coordination no. is 6 so sec. valency is 6
so ans. is 3,6