Question

Which of the following pairs of compounds are more stable?

• A. $\mathrm{K}_2\left[\mathrm{NiCl}_6\right],\left[\mathrm{Pt}(\mathrm{CN})_4\right]^{2-}$
• B. $NiCl_{4},PtCl_{4}$
• C. $\left[\mathrm{Ni}(\mathrm{CN})_4\right]^{2-}, \mathrm{K}_2\left[\mathrm{PtCl}_6\right]$
• D. $PtCl_{2},NiCl_{2}$

Answer 1

Answer: (C)

By comparing the value of ionization energies the thermodynamic stability of transition metal compound can be compared. Ionization value shows that $Ni\left(I I\right)$ compound are more stable then $Pt\left(\right.II\left.\right)$ compound while $Pt\left(\right.IV\left.\right)$ compound are relatively more stable than $Ni\left(\right.IV\left.\right)$ .