Question

What is the most likely reason that nonmetals are electrical insulators

Answer 1

Since valence shells in nonmetal atoms are almost full, the atoms attract electrons and hold them tightly to fill their valence shells.

Answer 2

Non metals are poor conductors of electricity as they have no free electrons in the outer most shell.

The poor conductors of the electricity is best to be used as insulators. These insulators can be used to protect the person from electrical shocks.

The valence shells in case of non metals are almost full, the atoms attracts the electrons and hold them tight and there is no electron left free to conduct electricity.

Hence, non metals are used as insulators.