Question

What is electron affinity a measure of?

Answer 1

This the enthalpy change associated with the formation of 1 mole of gaseous anions from 1 mole of gaseous atoms and 1 mole of electrons.

Explanation:

So electron affinity is the enthalpy change associated with the rxn:

`M(g) + e^(-) rarr M^(-)(g)`

How should this evolve across a Period from left to right?