Question

The ionic radii (in $A^{\circ }$) of $N^{3-}$, $O^{2-}$ and $F^{-}$ are respectively:

• A. $1.71,1.40,and1.36$
• B. $1.71,1.36,and1.40$
• C. $1.36,1.40,and1.71$
• D. $1.36,1.71,and1.40$

Answer 1

The correct option is A $1.71,1.40,and1.36$

For isoelectronic species, size of anion increases as negative charge increases. Thus the correct order is
${\underset{1.71}{N}}^{3-}>{\underset{1.40}{O}}^{2-}>{\underset{1.36}{F}}^{-}$