The energy gap of pure `Si` is `1.1 eV` The mobilities of electrons and holes are respectively `0.135 m^(2) V^(-1) s^(-1)` and `0.048 m^(2) V^(-1) s^(-1)` and can be taken as independent of temperature. The intrinsic carrier concentration is given by `n_(i) = n_(0) e^(-Eg//2kT)`.
Where `n_(0)` is a constant, `E_(g)` The gap width and `k` The Boltmann's constant whose vaue is `1.38 xx 10^(-23) JK^(-1)` The ratio of the electrical conductivities of `Si` at `600 K` and `300 K` is.

Explanation

conducting of semiconductor
`sigma=n_(e)emu_(e)+n_(h)emu_(h)`
Here `n_(e)=n_(h)=n_(i)`(pure semiconductor)
`sigma=n_(i)e(mu_(e)+mu_(h))`
`=e(mu_(e)+mu_(h))n_(i)`
`=e(mu_(e)+mu_(h))n_(0)e^(-E_(g)//2kT)`
`(sigma600)/(sigma300)=e^(-(E_g)/(2kxx600))/e^(-(E_g)/(2kxx300))=e^(E_(g)//1200k`
`=e^(1.1xx1.6xx10^(-19)//1200xx1.38xx10^(-23))`
`=e^(10.63)`