Question

Why is plastic a poor conductor?
A. They are non-reactive
B. They can melt
C. They have high number of free electron
D. They do not have free electron

Answer 1

Hint: Plastics are poor electrical conductors, which is why they are used as insulators on wires and in other places. Plastics are likely to make up the majority of current electronics packaging for reasons other than price. The number of electrons in an atom's outer shell determines its conductivity. As a result, metal is a fantastic conductor. However, in the face of a large current, plastic will simply melt.

Complete answer:
Based on their conductivity, the substances are classed as conductors or non-conductors.
The substance's free electrons are employed to conduct electricity. The electric charges are carried by free electrons. Electric charges cannot be carried if there are no free electrons, hence there is no electricity conduction. As, plastics have few or no free electrons since their molecules are formed up of lengthy chains of carbon and hydrogen atoms.
Hence the correct option is: (D) They do not have free electrons.

Additional Information:
Insulators are substances that do not conduct electricity or heat, and non-conductors are also known as insulators. Semiconductors are substances that fall between conductors and insulators and are neither good insulators nor good conductors.

Note:
It's worth noting that every insulator has a breakdown voltage at which it loses its insulating properties and turns into an excellent conductor. Air, for example, is an insulator, but a few thousand volts may easily break through it by ionising the air molecules into plasma, which is an efficient electrical conductor. At some point, every insulator will fail.