The set representing the correct order of ionic radii is

Options

A. `Li^(+) gt Be^(2+) gt Na^(+) gt Mg^(2+)`
B. `Li^(+) gt Na^(+) gt Mg^(2+) gt Be^(2+) `
C. `Mg^(2+) gt Be^(2+) gt Li^(+) gt Na^+`
D. `Na^(+) gt Li^(+) gt Mg^(2+) gt Be^(2+)`

Answer

D

Explanation

The di positive charge cation is smaller than mono positive charge cation due to more effective nuclear charge and ionic size decreases down the group.
`Na^(+) gt Li^+` (down the group)
`Mg^(2+) gt Be^(2+)` (down the group)