A small amount of acetonitrile (CH3CN) is dissolved in a large amount of water. Imagine separating this process into the four stages sketched below. (These sketches show only a portion of the substances, so you can see the density and distribution of atoms and molecules in them.)

b) mutualism

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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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