Introduced to this in AP Chemistry
What is it
The effective nuclear charge increases across a period. Distance between nucleus and valence electrons increases down a group. It is more difficult to remove the 2nd electron from a +1 ion than to remove the 1st electron from a neutral atom.
The thing that’s holding electrons around the nucleus is called the Coulomb’s Law
Neutrons hold the protons together that want to repel each other
We can use Coulomb’s Law to predict Ionization Energy
2 like charges = repel 2 unlike charges = attract
Ionization Energy - Amount of energy required to remove an electron
F = k (always going to be used conceptually not mathematically)