# How can chlorine be 'only' the third-most electronegative element yet have the highest electron affinity?

From Wikipedia:

It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the Pauling scale, behind only oxygen and fluorine.

I am confused....

P.S.: I naively assumed that 'electronegativity' was the same thing as 'electron affinity'.... Perhaps that is why I got several downvotes....

The first answer, which I 'checked', explained the difference...

Apparently, the somewhat vague concept of Linus Pauling's 'electronegativity' includes two concepts: Both the relative, quantified tendency to grab an electron and the relative, quantified tendency not to lose one.... Combined into the somewhat-quantified, relative concept of electronegativity.....

Fluorine is a rather small atom. The incoming electron is put into a region of space already crowded with electrons. So there is a significant amount of repulsion, which lessens the attraction the incoming electron feels, and so lessens the electron affinity. A similar reversal happens between Oxygen and Sulfur. The firs electron affinity of oxygen (-$$142 kJ/mol$$) is smaller that that of Sulfur (-$$200 kJ/mol$$), for the same reason.