Question

Which is correct order of size of $O^{-},O^{2-},F^{-}$ and $F$?

• A. $O^{2-}>O^{-}>F^{-}>F$
• B. $O^{-}>O^{2-}>F^{-}>F$
• C. $O^{2-}>F^{-}>F>O^{-}$
• D. $O^{2+}>F^{-}>O^{-}>F$

Answer 1

The correct option is A $O^{2-}>O^{-}>F^{-}>F$

As we move along a row, radius decreases and as we move down the group, radius increases.

As a particular atom gains an electron, size increases due to inter-electronic repulsions.

So, order is $O^{-}>F^{-}$.

Thus, $O^{2-}>O^{-}>F^{-}>F$.

Hence, option A is correct.