# How would you compare the formation of positive ions with the formation of negative ions in terms of energy changes?

Mar 19, 2018

Ionization energies, are associated with the LOSS of an electron, and the formation of a positive ion.....

#### Explanation:

Ionization energies, are associated with the LOSS of an electron, and the formation of a positive ion.....i.e.

$M \left(g\right) + \Delta \rightarrow {M}^{+} \left(g\right) + {e}^{-}$

And these should be an inherently ENDOTHERMIC process, i.e. we have to put energy in to separate the electron from the positively charged nuclear core.

On the other hand, the formation of negative ions represents a quantity that is measured by electron affinity....

$M \left(g\right) + {e}^{-} \rightarrow {M}^{-} \left(g\right)$

And the energy involved in this transition MAY be exothermic given an atom with a HIGH, unshielded nuclear charge...i.e. a non-metal. And we can look at the behaviour of the halogens as an example, whose electron affinities are exothermic....