Question:
The ionic radii of $\mathrm{O}_{2}{ }^{-}, \mathrm{F}^{-}, \mathrm{Na}^{+}$and $\mathrm{Mg}^{2+}$ are in the order :
Correct Option: , 4
Solution:
as $\frac{z}{e}$ ratio increases size decreases.
Thus correct ionic radii order is
$\mathrm{O}^{-2}>\mathrm{F}^{-}>\mathrm{Na}^{+}>\mathrm{Mg}^{2+}$
Therefore correct option is (4)