Ionic compounds can conduct electricity when dissolved in water or melted, because

a. the ions are fixed in place.
b. they have shared electrons.
c. the ions are free to move.
d. they have no ions to contribute to the solution.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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