Question

How many sigma and pi bonds do sp, sp2, sp3, sp3d, sp3d2 have?

Answer 1

Without knowing more context, it's not possible to know the number of `pi` bonds.

If you want to get the number of `pi` bonds, know what compound you're looking at, and just count them.

One pure double bond has one `sigma` and one `pi` bond, and one pure triple bond has one `sigma` and two `pi` bonds.

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From knowing the hybridization of the central atom, we can determine the number of `sigma` bonds around the central atom, but no more than that without more information.

Examples:

• `sp` hybridization in acetylene corresponds with two `sigma` bonds around one carbon.
  

• `sp^2` hybridization in ethene corresponds with three `sigma` bonds around one carbon.
  

• `sp^3` hybridization in methane corresponds with four `sigma` bonds around one carbon.
  

• `sp^3d` hybridization in `"PF"_5` corresponds with five `sigma` bonds around one phosphorus.
  

• `sp^3d^2` hybridization in `"SF"_6` corresponds with six `sigma` bonds around one sulfur.
  

You can see that the number of orbitals used in the hybridization spits out the same number of hybridized orbitals that can `sigma` bond. That is, you get five `sp^3d` orbitals, for example.

Therefore, the number of orbitals used in the hybridization is the number of `\mathbf(sigma)` bonds made around the central atom.