>>7623450nice bait
>>7621893Hybridization is a very simple and, in most cases, pretty accurate first approximation of carbon geometries across a wide variety of molecules. As a model it is still *very* useful to explain a wide variety of trends (potentials, pKa's, BDEs, etc.) so that's why it's still worth teaching.
When you get to things the model doesn't describe well (e.g., PCl5), that's where the idea of hybridization falls apart: it won't explain why two of the chlorines have longer bond lengths, nor will it explain why they have to be positioned in the apical positions of a trigonal bipyramidal structure. THAT is where you need MO theory to demonstrate the division of s/p character to each chlorine and describe the more exotic three center four electron bond.
