Question

Which of the following represents correct order of conductivity in solids?

• A. $K_{metal}>>K_{insulator}<K_{semiconductors}$
• B. $K_{metal}<<K_{insulator}<K_{semiconductors}$
• C. $K_{metal}<K_{semiconductors}>K_{insulator}\ne Zero$
• D. $K_{metal}\simeq K_{semiconductors}>K_{insulator}=Zero$

Answer 1

The correct option is A $K_{metal}>>K_{insulator}<K_{semiconductors}$

$\text{Analyzing the conductivity of metal}$

• Metals have free electrons in them, which helps largely with the conduction of electricity. So, they have the highest conductivity.
• Metals are solids with conductivities between ${10}^4$ and ${10}^{7}oh{m}^{-1}{m}^{-1}$ which is quite high, so they are considered as a good conductor of electricity.

$\text{Analyzing the conductivity of insulators}$

• Insulators do not have free electrons. So, electricity cannot pass through the insulators. So, their conductivity is at the lower side.
• Insulators are solids with low conductivities ranging from ${10}^{-20}$ to ${10}^{-10}oh{m}^{-1}{m}^{-1}$ .

$\text{Analyzing the conductivity of semiconductors}$

• Conductivity of semiconductors depends upon the temperature. At normal temperatures, they behave as insulators. But when temperature increases, the conductivity of semiconductors increases.
• Semiconductors are solids with conductivities in the intermediate range, between ${10}^{-6}$ and ${10}^{4}oh{m}^{-1}{m}^{-1}$.

So, the correct order of conductivity is:

$K_{metal}>>K_{insulator}<K_{semiconductors}$