Based on electronegativity differences, which bond is a polar covalent bond?

A bond in which the electronegativity difference between the atoms is between 0.4 and 1.7 is called a polar covalent bond.

A polar covalent bond is a covalent bond in which the atoms have an unequal attraction for electrons and so the sharing is unequal.

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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