Why is energy released when looking at electron affinity but absorbed when looking at ionization energy? I keep expecting the electron gained in electron affinity to bring energy along with it. I’d really appreciate some help on this topic 
To overcome the electrostatic force between the electron in the outermost shell and the nucleus, we need to provide energy to break that to remove the electron; this is the ionisation energy.
So we know that energy is supplied for removing an electron. This implies that energy will be released if an extra electron is ADDED to the atom. The amount of energy released when a neutral atom in its gaseous state accepts an electron and gets converted into a negatively charged ion is known as electron affinity.
Hope this helps!
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