2.67 part B

[Alex Kashou]

I understand that electron affinity is the energy released when an electron is added to an atom. I also understand the trend that as you go up and to the right of the periodic table electron affinity increased. Therefore, why does Carbon have a higher electron affinity than nitrogen?

[Lena Nguyen 2H]

For carbon and nitrogen, we would need to consider their electron configurations. Adding an electron to carbon would be adding it to an empty p-orbital, but for nitrogen, adding an electron means adding it to a p-orbital with an electron already inside it. This is more difficult because of electron repulsion since both have negative charges. So nitrogen has a lower electron affinity than carbon.

Example 2.4 explains this as well.

[Brigitte Phung 1F]

In Nitrogen, all three orbitals in the p subshell are half-filled with one electron each which makes it more stable than Carbon, which has two half-filled and one empty p-orbital. Thus, Carbon has a higher electron affinity than Nitrogen. Hope this helps!

[Ramya Lakkaraju 1B]

Generally atoms that have half or full orbitals are the most stable so they will not want to add electrons that easily.

[Emily Duggan 1F]

does this rule of half-filled being more stable and therefore lower electron affinities apply to the entirety of Group 15 or just nitrogen?