Give the o. n. of each of the elements magnesium and oxygen in the reactants and in the products. 2Mg + O22MgO

In reactant side, it's 0 and in product side, it's -2.

he would use the colour black

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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