Hybridisation

[paulo1913]

How can you tell what sort of hybridisation a molecule has?

[Comandante]

It depends on what level of chem you are

 

If you're just starting on hybridization and all that, then there are a few general rules, well more like, memorising and being able to explain some examples. But if you need to work these out yourself for a test or something then there are a few more examples.. and rules First thing would probably be to determine the shape of the molecule and then hybridization. Typical example would be nitrogen, which has 5 valence electrons, I've usually seen it bond with 3 other atoms and has a pair of electrons spare. This pair of electrons acts almost like another bond, but a bit stronger (repelling). What happens is that you need to determine the angles around the central atom at maximum spacement of other atoms in the molecule. And for the nitrogen I mentioned, the angles would be somewhat less than 109.5° - this they refer to as sp3 hybridization (exception would be N in amide bond, where it was experimentally found to be sp2 hybridization rather than sp3 by this guy: http://en.wikipedia.org/wiki/Linus_Pauling ). Basically to determine the angles you just have to work out where the atoms will be located when they push apart in space around the central atom, taking into acount valence pair of electrons such as that in nitrogen. For more accurate/detailed description of that refer to the http://en.wikipedia.org/wiki/VSEPR . For more info on hybridization.. again, refer to our almighty wiki ; http://en.wikipedia.org/wiki/Orbital_hybridisation