Energy bands in solids

2012 AIPMT-PRE 1 question

1. 1 Semiconductor Electronics: Materials, Devices and Simple Circuits
   C and Si both have same lattice structure, having 4 bonding electrons in each. However, C is insulator whereas Si is intrinsic semiconductor. This is because
   A The four bonding electrons in the case of C lie in the third orbit, whereas for Si they lie in the fourth orbit B In case of C the valence band is not completely filled at absolute zero temperature C In case of C the conduction band is partly filled even at absolute zero temperature D 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
   Check Answer