Lead is a metal, and metals are known for their excellent electrical conductivity. This is because metals have a "sea" of free electrons that can easily move throughout the material when an electric field is applied.

Sulfur, on the other hand, is a non-metal. Non-metals have tightly bound electrons that are not easily freed to carry electrical current. Therefore, sulfur is a poor conductor of electricity.

Here's a summary:

* Lead: Good conductor due to its free electrons.

* Sulfur: Poor conductor due to its tightly bound electrons.