Question

Which of the given ions has the highest electron affinity (EA) : $F^{-}$ or $C{l}^{-}$ ?

• A. $F^{-}$
• B. $C{l}^{-}$
• C. Both have same
• D. None of the above

Answer 1

The correct option is A $F^{-}$

$F^{-}$ ions has the highest electron affinity (EA). $F^{-}$ ions are smaller in size than $C{l}^{-}$ ions. When an electron is added to $F^{-}$, the inter electronic repulsion is higher than when an electron is added to $C{l}^{-}$ ions. Thus more energy is required to add electron to $F^{-}$ ion than to $C{l}^{-}$ ion.