Question

Which one of the following is correct order of the size?

• A. $I >I^{-} >I^{+}$
• B. $I >I^{+} >I^{-}$
• C. $I^{+} >I^{-} >I$
• D. $I^{-} >I >I^{+}$

Answer 1

Answer: (D)

The size of the cation is always smaller than that of its parent atom and size of the anion is always larger than that of its parent atom.
$\therefore $ Size of the cation $\propto \frac{1}{\text { magnitude of positive charge }}$
Size of the anion $\propto$ magnitude of negative charge
Hence, the correct order of the size is $I^{-}>I+I^{+}$