Question

Which approach is better to explaining multiple bonds, valance bond or molecular orbital theory? Explain.

Answer 1

http://www.science.uwaterloo.ca/~cchieh/cact/c120/hybrid.html

Answer 2

It may be a matter of taste, to some extent. Both approaches can certainly accomodate the concept of multiple bonds. I might argue for the MO approach, for two reasons: (1) it can accomodate noninteger bond orders, for example it can easily explain the fact that the two C-O bonds in the acetate anion are equivalent and have a bonding order between 1 and 2. VB theory can only accomodate these sorts of things by introducing resonance structures. (2) MO theory is simply a more realistic and accurate way of looking at bonding in molecules. The only reason we use VB at all is because it is faster and more intuitive when you are just considering how a big framework of atoms is put together.