Question

Addition of excess potassium iodide solution to a solution of mercuric chloride gives the halide complex :

• A. tetrahedral $K_2\left[Hg{I}_4\right]$
• B. trigonal $K_2\left[Hg{I}_3\right]$
• C. linear ${Hg}_2{I}_2$
• D. square planar $K_2\left[Hg{Cl}_2{I}_2\right]$

Answer 1

The correct option is A tetrahedral $K_2\left[Hg{I}_4\right]$

$\Delta H=0,Hg{Cl}_2+4KI⟶K_2\left[Hg{I}_4\right]+2KCl$

$Hg=\left[Xe\right]4f^{14}5d^{10}6s^2$

${Hg}^{2+}=\left[Xe\right]4f^{14}5d^{10}6s^0$

Hence, the correct option is $\text{A}$