Question

Solid copper conducts electricity through electron whereas copper solution conducts electricity through ions. Comment.

Answer 1

solid copper is a bad electrolyte and good conductor of electricity in solid state ie electricity is produced by the movement of electrons.

copper as ion is a good electrolyte ie electricity is produced by the movement of free ions

Answer 2

Solid copper (such as copper wire) contains free electrons in the outermost shells (as in most metals) and hence conducts electricity through the motion of these electrons.

Whereas in copper salt solution (such as CuSO4), Cu+ ions are formed in the solution. We know ions are charged particles and hence they conduct electricity.