How do i know how many covalent bonds are made by each atom?

A covalent bond is a strong bond between two non-metal atoms. It consists of a shared pair of electrons. A covalent bond can be represented by a straight line or dot-and-cross diagram. Hydrogen and chlorine can each form one covalent bond, oxygen two bonds, nitrogen three, while carbon can form four bonds.

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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