Question

(a) Explain why, ionic compounds conduct electricity in solution whereas covalent compounds do not conduct electricity.
(b) Which of the following will conduct electricity and which not?
MgCl₂, CCl₄, NaCl, CS₂, Na₂S
Give reasons for your choice.

Answer 1

(a) An ionic compound consists of ions held by strong forces in solid state. But when an ionic compound dissolves in water to form a solution, the constituent ions get separated and they disperse across the solution. This helps in conducting an electric current through the solution. Covalent compounds are formed by the sharing of electrons. So ions that conduct electricity are not involved in these compounds. Hence covalent compounds do not conduct electricity.

(b) The compounds that conduct electricity are MgCl₂, NaCl and Na₂S. These compounds are ionic in nature So conduct electricity. The compounds that do not conduct electricity are CS₂ and CCl₄. These compounds are covalent in nature. Hence they do not conduct electricity.