CHEMISTRY COMMUNITY

Is there a reason why sigma bonds are stronger than pi bonds?

It has to do with the orientation of overlapped orbitals. Sigma bonds are formed by end-to-end overlapping while pi bonds are formed by lateral overlapping. The extent of overlapping is maximized in sigma bonds and is therefore stronger than pi bonds.

The overlap of pi bonds are smaller than the overlap of sigma bonds, making pi bonds easier to break apart. Hence, sigma bonds are stronger.

Sigma bonds overlap more closely across the internuclear axis. The concentration of electrons brings the nuclei closer together (harder to detach).

sigma bonds are stronger because the overlap of the sigma bond is smaller than the pi bond so it is harder to break apart.

You can also think of pi bonds as relating to double bonds while sigma bonds only refer to single bonds.