(c) Suggest a reason why substance E does not conduct electricity in both solid and
molten states.

Substance E does not conduct electricity in both solid and molten states because of very low melting and boiling points.

In both solid and molten state free electrons are required to conduct electricity. substance E has low boiling and melting point which means substance will have relatively weak bonds. Because of weak bonds substance E might not have much free electron in its outermost shell that can cause the electric current by their coordinated movement.

Hence, substance E is unable to conduct in both melting and molten state.

the answer is 75.0%.