Q. $C$ and $Si$ both have same lattice structure, having 4 bonding electrons in each. However, $C$ is insulator where as $Si$ is intrinsic semiconductor. This is because
A) In case of $C$ the valance band is not completely filled at absolute zero temperature
B) In case of $C$ the conduction band is partly filled even at absolute zero temperature
C) The four bonding electrons in the case of $C$ lie in the second orbit, whereas in the case of $Si$ they lie in the third
D) The four bonding electrons in the case of $C$ lie in the third orbit, whereas for Si they lie in the fourth orbit
Explanation
(c) $\ ^{6}C = 1S^{2},\ 2S^{2}\ 2P^{2}$
$\ ^{14}Si = 1S^{2},2S^{2}\ 2p^{6},\ 3S^{2}\ 3P^{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.