The total number of electrons in a neutral atom of every element is always equal to the atom's A) mass number
B) number of protons
C) number of neutrons
D) number of atomic particles

Number of Protons

Explanation:

The number of Protons is always equivalent to the amount of electrons that are on the outside of the atom

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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