Question

Which of the following ion has smallest ionic radius

• A.
• B.
• C.
• D.

Answer 1

The correct option is D

Lets calculate the number of electrons :

$K^{+}\to 18electrons$

$C{a}^{2+}\to 18electrons$

$T{i}^{3+}\to 18electrons$

$T{i}^{4+}\to 18electrons$

So, therefore, they all are isoelectronic species.All are cations. Size of the cation decreases with increase in charge on it.Therfore correct optiopn is (d)