What information in a balanced chemical equation shows how many moles of a reactant are involved in the reaction?

Coefficients

Explanation: The coefficients in a balanced chemical equation tell you how many moles of reactants you'll require and how many moles of product you'll be able to make.

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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