Question

Metals are good conductors of electricity because of which of the following reasons?
A. metals have free electrons
B. metals have free ions
C. metals have free atoms
D. none of the above

Answer 1

conductivity of metals or ionic compounds depend upon the presence of free electrons or free ions. Metal form crystal lattice. In which metal atoms are bound by electrostatic forces. The conductivity of the ionic compound depends upon the ionization of that compound in aqueous solution.

Complete Step by step answer: Conductivity is the ability to conduct electricity which depends upon the presence of free electrons as well as free ions.
The electrons present in the outermost shell of the metal are very loosely bound because the nucleus has very little attraction on the outermost shell electrons. Thus, on applying heat the electrons of metal become mobile and conduct electricity. So, the metals conduct electricity due to the presence of free electrons.
So, metals are good conductors of electricity because metals have free electrons.

Therefore, option (A) metals have free electrons, is correct.

Note: The metal conduct electricity in both molten as well as in solid state. The conductivity of metal is due to the free electrons which present in both the solid and molten state whereas the ionic compound conduct electricity only in solution because conductivity of the ionic compound is due to ions which are present in solid state but becomes free only in molten sate. Free electrons increase the conductivity of metal increases. The small ions become more hydrated in aqueous solution so, the conductivity decreases on decreasing the size of the ion.