Why is benzene nonpolar?

1 Answer
Nov 9, 2015

Benzene is nonpolar because it is a symmetrical molecule in which all the bond dipoles cancel.


The structure of benzene is


It is a flat molecule with the shape of a regular hexagon.

We could say that benzene is nonpolar because it is a hydrocarbon that contains only #"C-C"# and #"C-H"# bonds, and hydrocarbons are nonpolar.

But #"C"# is slightly more electronegative than #"H"# (by 0.35 units), so a #"C-H"# bond is very slightly polar and has a small dipole moment.

However, each #"C-H"# bond has a partner that points in exactly the opposite direction.

The bond dipoles cancel exactly, so benzene has a zero dipole moment.

This makes benzene a nonpolar molecule.