Question

Why do the halogen atoms have the greatest electron affinity?

Answer 1

Answer:

We know that electron affinity decreases down the group(since the number of shells increases down a group and hence the nucleus attracts the incoming electrons with a lesser force).

So, the answer should be fluorine, but the size of fluorine atom being very small, there is strong inter electronic repulsion and not much force is felt by the incoming electron.

Hence the electron affinity of chlorine(which is just below fluorine) is the highest among halogens

Answer 2

halogens atoms have greatest electron affinity because as atomic size decreses the nuclear charge increases