how many unhybridized p orbitals?

Question

A) If the valence atomic orbital of an atom are sp hybridized, how many unhybridized p orbitals remain in the valence shell? How many pi bonds can the atom form?

B) How many sigma and pi bonds are generally part of a triple bond?

C) How do multiple bonds introduce ridigity into molecules?

Answer 1

1) sp hybridized carbons always means a triple bond. Of three available p orbitals only one is hypridized to make the sp. So two unhybridized p orbitals remain. The atom therefore, can form two pi bonds, one with each unhyridized orbital.
2) A triple bond always has one sigma bond and two pi bonds. Sigma bonds are the result of interactions between orbitals that point directly toward eachother. The sigma bond comes from the sp orbital. Pi bonds come from interaction between orbitals that are parallel to eachother.
3) A molecule freely rotates around a sigma bond with very little energy. However in a double bond if the molecule cannot rotate because the p orbitals used to create the bond will become perpendicular -- rather than parallel. This places one p orbital in the node of the other. The node is the location of the p orbital that doesn't have any electron density which would be contridictory. It is for the same reason impossible to rotated around a triple bond.

Answer 2

Unhybridized P Orbital

Answer 3

a)out of three p orbitals, one is sp hybridised. so unhybridised are two. two pi bonds can be formed
b) one sigma and two pi bonds
c) by reducing or even eliminating free rotation about the bond.

Answer 4

2
2
It would be easier to twist around a single σ bond