Pure silicon at room temperature contains approximately 1.0 X 1016 free electrons per cu...

Pure silicon at room temperature contains approximately 1.0 X 10¹⁶ free electrons per cubic meter. (a) Referring to Table 25.1, calculate the mean free time τ for silicon at room temperature. (b) Your answer in part (a) is much greater than the mean free time for copper given in Example 25.11. Why, then, does pure silicon have such a high resistivity compared to copper?