Periods 15 and 14 relationship

[Kristina Mercolino 3C]

What is the relationship between these two periods for electron affinity? One of the answers for a homework problem in Ch. 2 stated that carbon has a higher electron affinity than nitrogen. Why is that?

[Chris_Rudewicz_3H]

I think you meant Groups 15 and 14.
From what I have seen online, there is no real pattern or trend for groups 15 and 14. One thing for sure though is that Nitrogen has a very low electron affinity value.

[Rachel Wile 2D]

If you draw the electron configuration for each and specifically look at the 2p orbital you will see that Nitrogen has a half-filled p-shell, which is more stable than Carbon which is one away from a half filled p-shell. Carbon wants the electron more than Nitrogen to attain the stability.