Modern atomic theory states that the atom on diffuse cloud surrounding a small dense nucleus identifying which particle is in the nucleus

answer; i believe that the correct answer is (a); a large rock being weathered by wind and rain;

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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