question_answer

Carbon and silicon are known to have similar lattice structures. However, the four bonding electrons of carbon are present in second orbit while those of silicon are present in its third orbit. How does this difference result in a difference in their electrical conductivities?               

Answer:

                The energy required to take out an electron from Si atom is much smaller than that in case of C atom. Hence the number of free electrons for conduction is Si is quite significant but negligibly small for C. Consequently the conductivity of silicon is much greater than that of carbon.