What was Rutherford's model of the atom missing?

Explanation:

Rutherford's model was missing energy levels for electrons. Planetary model‐аElectrons orbit the nucleus like planets around the sun. Bohr placed the electrons in energy levels (shells) outside of the nucleus.

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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