Chapter 29, Problem 63A

To determine

To explain conduction of electricity by graphite is more like copper or more like silicon.

Explanation of Solution

Introduction:

As temperature rises, electrons gain energy to jump the forbidden gap in a solid and thus conductivity of the solid will increase.

Graphite has a small energy gap due to its crystalline nature and therefore is a good conductor of electricity. Its resistance decreases as temperature rises. Therefore, at high temperatures, graphite’s conductivity increases.

Copper being a metal is also a good conductor but it is not as stable as graphite at high temperature.

Like graphite, silicon’s conductivity also increases at high temperatures as the electron’s gains enough energy to jump the forbidden gap. Hence, graphite conducts electricity more like silicon than copper.

Conclusion:

Graphite conducts more like silicon than copper as it is more stable at higher temperatures.