The correct order of decreasing radius of aquated `Na^(+), K^(+) " and " Li^(+)` is:

Options

A. `Na^(+) (aq) gt K^(+)(aq) gt Li^(+)(aq)`
B. `K^(+)(aq) gt Na^(+)(aq) gt Li^(+)(aq)`
C. `Li^(+)(aq) gt Na^(+)(aq) gt K^(+) (aq)`
D. `K^(+) (aq) gt Li^(+)(aq) gt Na^(+) (aq)`

Answer

C

Explanation

Size ` = Li^(+) (g) lt Na^(+) (g) lt K^(+) (g)` but in aqueous medium the order reverses because the charged density of is highest among alkali metal ions hence its effective size is highest (due to more ion dipole interaction)