Question

What elements have essentially no tendency to accept electrons (referring to electron affinity)?

Answer 1

The noble gas elements.

Explanation:

Neon, for example, has its outer shell full, because it's a noble gas. It has already satisfied its filling of electrons, so it doesn't want anymore (or any less). This is true of all noble gases. In fact, the filling of the outer shell is desired by the other elements, so they tend to form bonds that allow them to be more like the noble gases.

The following have zero or positive electron affinity:

Helium
Neon
Argon
Krypton
Xenon
Radon