Determine the electron pair of molecular geometries for NH3.
In order to find the geometries of a molecule,
I first need to know the Lewis structure.
So I'm going to first look and see how many valence electrons I have in NH3.
So I know how many electrons need to be in my Lewis structure.
Nitrogen has five and each hydrogen has one for
a total of eight electrons in my structure.
So now I'm going to draw nitrogen with single bonds to hydrogen,
rRemember hydrogen's always a terminal atom.
I've used up six of my electrons,
my hydrogen's don't want an octet they only want two electrons around them.
And so I'm only going to have two electrons left that
will go on the nitrogen atom, because the Hydrogens don't want any more electrons.
I see that I have the general form AX3E or
a total of four groups around my central atom.
So my electron pair geometry is going to be tetrahedral.