Question

Crystalline sodium chloride is a bad conductor of electricity while molten NaCl and its aqueous solution conduct electricity. This is because:

• A. crystalline sodium chloride contains molecules only
• B. the ions present in it are not free to move in solid state
• C. sodium chloride is covalent crystal
• D. solid substances do not conduct electricity

Answer 1

The correct option is B the ions present in it are not free to move in solid state

In crystalline solids, the ions are tightly bound by strong coulombic force of attraction having greater interatomic interaction and less interparticle space. ${Na}^{+}and{Cl}^{-}$ ions are free to move only in molten state or aqueous solution.