I'm learning how to apply the VSEPR theory to Lewis structures and in my homework I'm being asked to provide the hybridization of the central atom in each Lewis structure I've drawn.
I've drawn out the Lewis structure for all the required compounds and figured out the arrangements of the electron regions, and figured out the shape of each molecule. I'm being asked to figure out the hybridization of the central atom of various molecules.
There is a sample question with all the answers filled out: NH3
It has a hybridization of sp3.
Where does this come from? I understand how to figure out the standard orbitals for an atom, but I'm lost with hybridization.
My textbook uses CH4 as an example. Carbon has 2s2 2p2, but in this molecule, it has four sp3. I understand the purpose of four (there are four hydrogens), but where did the 3 in sp3 come from?
How would I figure out something more complicated like H2CO?