Semiconductors can become conductive if their temperature is raised sufficiently to populate the (empty) conduction band from the highest filled levels in the valence band. The ratio of the populations in the lowest level of the conduction band to that of the highest level in the valence band is

nconduction/ nvalence=gconduction/ gvalence e^−ΔE/kBT

where ΔE is the band gap, which is 1.12 eV for Si and 5.5 eV for diamond. Assume for simplicity that the ratio of the degeneracies is one and that the semiconductor becomes sufficiently conductive when

nconduction/ nvalence=5.5×10^−7.

a. At what what temperature will diamond become sufficiently conductive?
b. At what temperature will silicon become sufficiently conductive?