Which statement describes both homogeneous mixtures and heterogeneous mixtures?
a. their components can be distinguished visually
b. their components are combined in a fixed ratio
c. their components can be separated by physical processes
d. they always contain a liquid component
e. they are considered to be pure substances

C. Their components can be separated by physical processes.

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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