Question

Metal are good conductor of heat . Justify the statement.

Answer 1

Metals are good conductors of heat. There are two reasons for this: the close packing of the metal ions in the lattice. the delocalised electrons can carry kinetic energy through the lattice.

Answer 2

Electric current is due to the flow of electrons, that is around the nucleus of the atom of the conductor. Searching for the path of least resistance.

Same way electrons help to conduct heat. Heat elevates the energy level of electron. Then electron falls to its stable level releasing the energy, which in turn elevates the energy level of nearby electron. And chain reaction searching for the least resistance to the cold side.

So these free electrons with certain energy levels in conductors are the reason for good conduction of electric current and heat.