Question

Which of the following statements is true?

A) metals have large thermal conductivitits because they expand when heated

B) metals have high electrical conductivities because the electrons in the metal are delocalized

C) metals have high electrical conductivities because they are denser than other solids

D) metals have small thermal conductivities because the delocaloized electrons cannot easily transfer the kinetic energy imparted to then metal from heat

Answer 1

Metals are good conductor of heat because:

Conduction of heat occurs in a substance when the substance is heated and the particles of the substance gain some energy and starts vibrating. These vibrating molecules bump into the nearby particles and then transfer some of their vibrational energy to them. This process then continues and passes energy from hot end of substance down to colder end of substance.
The electrons in the metal are delocalised and thus, they are freely moving electrons. So when these electrons gain heat energy, they vibrate more quickly and move around and conducts heat, this means that these electrons pass on the energy to the other molecules more quickly.

Metals are good conductor of electricity because:
As mentioned above, metals contain free moving delocalized electrons. When the electric voltage is applied, the electrons start moving from the negative side to the positive side and thus conducts electricity.

Option B is only correct.