Question

Generally, non-metals are not conductors of electricity, which of the following is a good conductor of electricity?
A. Diamond
B. Graphite
C. Sulphur
D. Fullerene

Answer 1

Hint: For the conduction of electricity, free electrons should be present in the structure. Among the above given options, the structure containing free electrons is the good conductor of electricity.

Complete step by step answer:
We know that free electrons are responsible for the conduction of electricity. As you look to the structure of graphite, it is an allotropic form of carbon. Among the four electrons of the carbon, only three of them participate in bonding in the graphite. The remaining one free electron is responsible for the conduction of electricity. Since graphite has a free electron, it is the good conductor of electricity among the given options.

Therefore, the correct option is (b).

Additional Information:
Graphite has a layered planar structure. Carbon atoms in the plane are bonded covalently with only three of the four potential bonding sites. The fourth electron is free to migrate in the plane making graphite electrically conductive.
Diamond is a solid form of the element carbon with its atom arranged in a crystal structure called diamond cubic. Diamond has the highest hardness and thermal conductivity of any natural material, properties that are utilized in major industrial applications such as cutting and polishing tools.

Note: You should notice that Diamond, Graphite and Fullerene are the three allotropic forms of carbon. We know that allotropes are different forms of existence of the same element. Also it shows different physical and chemical properties. Here, only one allotrope, Graphite showing the electrical conductivity while others not conducting electricity.