Carbon is allowed to diffuse through a steel plate 10-mm thick. The concentrations of carbon at the two faces are 0.815 and 0.277 kg C/m3 Fe, which are maintained constant. If the preexponential and activation energy are 6.5 × 10-7 m2/s and 82 kJ/mol, respectively, calculate the temperature (in K) at which the diffusion flux is 3.2 × 10-9 kg/(m2-s).

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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