Heat of Hydration of Na^(+) (size 102 Pm) = - 397J Kj mol^(-1) whereas Ca^(2+) (size 100 Pm) = - 1650 kJ mol^(-1). Explain the difference.

Heat of Hydration of Na^(+) (size 102 Pm) = - 397J Kj mol^(-1) whereas

1.	Heat of Hydration of Na^(+) (size 102 Pm) = - 397J Kj mol^(-1) whereas Ca^(2+) (size 100 Pm) = - 1650 kJ mol^(-1). Explain the difference.
Answer» Solution :`Ca^(2+)` is smaller in size then `Na^(+)` and ALSO it has HIGHER charge therefore, its HYDRATION ENERGY is more than that of `Na^(+)`