Contrast ionization energy from electron affinity.

Ionization energy : energy required to take out an electron from the valance orbital of an atom.

Electron affinity: electron affinity of an atom measures the amount of energy released when an electron is forcibly entered or pushed into the valence orbital of an atom.

Ionization energy is the energy required to make an atom into a positive ion. Electron affinity is the energy released when an atom becomes a negative ion.

ionization energy is what is required to remove one electron from a normal gaseous atom to produce a +1 anion of that atom.

electron affinity is the energy required to remove one electron from a gaseous -1 anion of an atom to produce a normal gaseous atom.

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