How many valence electrons do insulators typically contain?

Insulators typically contain 7 or 8 valence electrons. This is significant because materials with 7 or 8 valence electrons are generally considered to be stable and non-reactive, which is a characteristic feature of insulators. The stability arises from their filled or nearly filled outer electron shells, making it difficult for them to conduct electricity.

In insulators, electrons are tightly bound to their atoms and cannot move freely. This restricts the flow of electric current, which is why insulators are effective at preventing the passage of electricity. For instance, noble gases like neon and argon, which have a complete outer shell of 8 valence electrons, are excellent insulators. Various other non-metals also display similar characteristics, thereby contributing to their classification as insulators.

The presence of fewer valence electrons, as in the other options, suggests a higher tendency to bond or react, which is characteristic of conductors and semiconductors rather than insulators.