Chemistry- Electron Affinity very confused

[Null_]

Homework Statement

Rank the atoms in electron affinity, from smallest to largest.

Homework Equations

none

The Attempt at a Solution

G has the highest energy, followed by H then K. I looked at the diagram and saw that-
G= 1s^2 2s^1 (Li)
H= 1s^1 (H)
K= 1s^2 (He)

I know that ionization energy and electron affinity both are very high at F. There was a question about the IE, and I got it right as GHK. I thought that IE and EA were related to each other...IE is the want to become a cation (Which the top right surely doesn't want to do), and EA is the change in E when an e- is added...adding an e- to F takes a lot of E, but it's very stable.

I thought that the EA from low to high is the same as IE (GHK). I don't see why it isn't.

 

[zhermes]

They tend to follow the same trend, because they both measure how much an atom 'likes' electrons. The details are a little different however. You're definitely on the right track: IE is how much energy is required to remove an electron, and EA is how much energy is gained when an electron is added.

Looking at the atoms in the figure, compare the energy of the current state with the energy of adding another electron (think about the octet rule mostly); which atom would be 'happiest' to gain an electron?