Briefly explain the difference between self-diffusion and interdiffusion.

(a)Compare interstitial and vacancy atomic mechanisms for diffusion.
(b)Cite two reasons why interstitial diffusion is normally more rapid than vacancy diffusion.

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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