The correct sequence which shows decreasing order of the ionic radii of the elements is

Options

A. `AI^(3+) gt Mg^(2+) gt Na^(+) gt F^(-) gt O^(2-)`
B. `Na^(+) gt Mg^(2+) gt AI^(3-) gt O^(2-) gt F`
C. `Na^(+) gt F^(-) gt Mg^(2+) gt O^(2-) gt AI^(3+)`
D. `O^(2-) gt F^(-) gt Na^(-) gt Mg^(2+) gt AI^(3-)`

Answer

D

Explanation

For isoelectronic species, ionic radii `prop (1)/("nuclear charge")`.
So, correct order of ionic radii is `._(8)O^(2-) gt _(9)F^(-) gt _(11)Na^(+) gt _(12)Mg^(2+) gt _(13)AI^(3+)`