What is the hybridization of the central atom of each of the following molecules? a.) h2o b.) pbr5 c.) cocl2? you so much!

 The notion of hybrid orbitals was "invented" by Linus Pauling in 1931 to explain the observed geometry of mostly organic molecules. Today, we find that hybrid orbitals are pretty much confined to the central atoms found in the second period of the periodic table. Periods 3 and up not so much. 

(a) H2O O is the central atom, tetrahedral, sp3 hybridization 
(b) PBr5 P is the central atom, maybe sp2 for the three equatorial bonds * 
(c) COCl2.. C is the central atom, trigonal planar, sp2 hybridization 

The correct name for n3-ion should be azide.