What type of material typically has a high number of valence electrons, making it a poor conductor of electricity?

Insulators are materials that possess a high number of valence electrons, which contributes to their poor conductivity of electricity. In these materials, the valence electrons are tightly bound to their respective atoms, making it difficult for them to move freely through the material. This tight binding prevents the flow of electric current, characterizing insulators as substances that do not allow electricity to pass through easily.

In contrast, materials classified as metals typically have only a few valence electrons, which facilitates easier movement of electrons and therefore allows them to conduct electricity effectively. Semiconductors have properties that fall between those of insulators and conductors, as they can conduct electricity under certain conditions but generally have a higher resistance compared to metals. Conductors, as the name implies, are materials that readily allow electric charge to flow due to their free-moving electrons.

Thus, insulators are specifically known for their inability to conduct electricity, primarily due to their high number of valence electrons, which are not free to move.