Question

For Ni and Pt different IP in $MJmo{l}^{-1}$ are given below
$\underset{–}{(IP{)}_1+(IP{)}_2}$ $\underset{–}{(IP{)}_3+(IP{)}_4}$
$Ni$ $2.49$ $8.80$
$Pt$ $2.60$ $6.70$
hence,

• A. nickel (II) compounds tend to be thermodynamically more stable than platinum (II)
• B. platinum (IV) compounds tend to be more stable than nickel (IV)
• C. both (a) and (b) are correct
• D. none of the above is correct

Answer 1

The correct option is C both (a) and (b) are correct

The thermodynamic stability is dependent on value of ionisation enthalpy. As the value of ionisation enthalpy increases the thermal stability increases.

The sum of first and second ionization enthalpies for Ni(II) is lesser as compared to that of Pt(II) . Hence, nickel (II) compounds tend to be thermodynamically more stable than platinum (II).
On the other hand, The sum of first four ionization enthalpies for Ni(IV) is more than that of Pt(IV) . Platinum (IV) compounds tend to be more stable than nickel (IV)