12.97P - Chemistry: Molecular Nature Of Matter And Change

Question

Predict the effect (if any) of a decrease in temperature on the electrical conductivity of (a) silicon; (b) lead; (c) germanium.

Step-by-Step Solution

Answer

1. Silicon is a semiconductor
2. Lead is an insulator
3. Germanium is a semiconductor

Step 1: Classification of elements

Conductors are the elements that have a very high conductivity range of the order 10⁴ to 10⁶ S/cm. On the other hand, insulators have very low conductivity in the range 10^-4 to 10^-6 S/cm. Semiconductors have conductivity in the intermediate range.

Step 2: Classification of given elements

1. Silicon is a semiconductor with four valance electrons that can be converted into a conductor by doping.
2. Lead is an insulator. Although there are some studies that have shown that the formation of lead oxide does not allow electricity to flow through it.
3. Germanium is a semiconductor with four electrons in the outer subshell