Question

In the isoelectronic species the ionic radii $\mathring{A}$ of $N^{3-}$, $Ne$ and $A{l}^{+3}$ are respectively given by:

• A. $N^{3-}<A{l}^{3+}<Ne$
• B. $Ne<A{l}^{3+}<N^{3-}$
• C. $A{l}^{3+}<Ne<N^{3-}$
• D. $A{l}^{3+}<N^{3-}<Ne$

Answer 1

The correct option is C $A{l}^{3+}<Ne<N^{3-}$

The size of isoelectronic species is larger for negative ions and smaller for positive ions. Thus $N^{3-}>Ne>{Al}^{3+}$. Thus this order is satisfied in option C alone.