[Kevin248]

Hi! I thought I had gotten past and understood the whole concept of ions but 2 questions in my textbook made me question that.

The questions were: What is an atoms "ionization energy", and what does it mean when an atom is ionized?

I replied: An ionized atom is when one or more electrons either is added or leaves an atom, leaving the atom either positively or negatively charged. An atoms ionization energy is the energy it would take for such a process to happen

But the answer in the textbook was:

Ionized atom: An atom that has lost an electron

Ionization energy: The energy it would take for an electron to be so far removed from the nucleus that it no longer is attached to the atom.


This confuses me, since ions can be both negatively and positively charged? Why is the answer only about positive ions? Have I missed something?

[Ben111]

The word ioniziation energy is used for getting cathions. For anions an other word is used called electron affinity.

[Corribus]

@OP

You are right that the process of ionization can refer to gaining or losing an electron. So is rather ambiguous and a little confusing that "ionization energy" is commonly understood to be the energy for something (most often a neutral atom) to lose a single electron.