Atomic Radius

[lilyhoke 2E]

Hi, after completing the week 2, 3, and 4 achieve problems, I still feel as though I don’t fully understand the concept of how the anion or cation of an atom affects its atomic radius. My friend helped me through question 28, but would anyone be able to walk me through how to work this out?

[Jaden 14B 3F]

Atomic radius is determined by the number of electrons an atom possesses. An atom that has more electrons will have a larger radius. Electron affinity is determined by how many protons there are in relation to the electrons, and an atom with more protons per electron will have a higher electron affinity, and a smaller atomic radius. In this case, all these atoms have the same number of electrons, though the atoms with more protons will have a higher affinity and will have a smaller atomic radius.