Question

Why don’t ionic compounds have electrical conductivity as a solid but do as a liquid?

Answer 1

Hint: Ionic solids or compounds are types of solid compounds which are composed by combination of oppositely charged ions. In ionic compounds positive and negative ions are arranged in a regular fashion throughout the solid.

Complete answer:
Conductivity is the property of any compound to conduct the electricity through it. Compounds which allow movement of charged particles from one position to another under the influence of electricity are good conductors of electricity. While those compounds which are devoid of any charged particles to move under the electricity are referred to as bad conductors of electricity.
Ionic solids contain charged particles in form of cations and anions but in their solid state these ions are not allowed to move from one position to another even under the influence of external electricity supply. Therefore, due to lack of any movement of these charged ions, ionic compounds act as bad conductors of electricity in solid state.
When we convert ionic solid into liquid by molting, or by dissolving them in water, cation and anions present in compounds are released and free to move throughout the solution. Now when we apply electric fields in liquid these charged ions move in opposite directions and conduct electricity.
Therefore, ionic solid acts as a good conductor of electricity in liquid state.
For example: sodium chloride $\left(NaCl\right)$ is bad conductor of electricity in its solid state but when we dissolve it into water, it dissociated into ions $\left(N{a}^{+}\right)$ and $\left(C{l}^{-}\right)$. These ions are further responsible for conducting electricity.

Note:
Solids may be of different types depending upon their constituent’s particles like molecular solids which are composed of molecules $\left(HCl,S{O}_2\right)$. Metallic solids which are made up of metal atoms $\left(Ni,Cu\right)$ and covalent solids which are made up of non-polar atoms (diamond).