Question

Which of the following series is arranged in order of increasing ionic radius ?

• A. $M{g}^{2+}<S^{2-}<C{l}^{-}<K^{+}<C{a}^{2+}$
• B. $M{g}^{2+}<C{a}^{2+}<K^{+}<C{l}^{-}<S^{2-}$
• C. $S^{2-}<C{l}^{-}<K^{+}<M{g}^{2+}<C{a}^{2+}$
• D. $S^{2-}<M{g}^{2+}<C{a}^{2+}<C{l}^{-}<K^{+}$

Answer 1

The correct option is B $M{g}^{2+}<C{a}^{2+}<K^{+}<C{l}^{-}<S^{2-}$

More the negative charge, larger will be the ionic radius and more the positive charge, smaller will be the ionic radius and down the group size increases and along the period from left the size decreases.

Therefore, $M{g}^{2+}<C{a}^{2+}<K^{+}<C{l}^{-}<S^{2-}$
Thus, option (b) is correct.