`Cu^(2+)` has a stronger polarising power than that of `Ca^(2+)` because

Options

A. `Ca^(2+)` ion is saller than `Ca^(2+)`ion
B. `Ca^(2+)`ionhas inert gas configuration whereas `Cu^(2+)` ion does not
C. copper shows valency ,calcium does not
D. `Cu^(2+)` ion is smaller than `Ca^(2+)` ion and the d-electrons in `Cu^(2+)`ion shield the nucleus poorly

Answer

A

Explanation

It is due to screening effect based on Fajans' rule smaller the cationic size, greater the polarising power results smaller size of `Cu^(2+),(Cu^(2+)ltCa^(2+))`
Presence of d-orbital electrons `3d^(10) "in" Cu^(2+)` means larger polarising power.