Question

Which is a good conductor of heat?

• A. graphite
• B. diamond
• C. iodine
• D. none of these

Answer 1

The correct option is A

graphite

The explanation for the correct option -

• Substances that have high thermal conductivity, that is, conduct heat easily are known as good conductors of heat.
• Generally, all the non-metals are poor conductors of heat except Graphite.
• Out of the four valence electrons present in the Carbon atom, only three are used in bonding in graphite.
• Due to which there is one free electron in Graphite that makes Graphite a good conductor of heat and electricity.

The explanation for the incorrect options -

• Option B is incorrect because, in diamond, all bonds of a Carbon atom are other carbon atoms. This makes a diamond a bad conductor of heat and electricity and the hardest non-metal.
• Option C is incorrect because its electrons are tightly bound in covalent bonds, iodine is not a good conductor of electricity (the bonds between two iodine atoms to form a molecule of iodine (${\mathrm{I}}_2$).

Hence, Option A is the correct answer.