A conductor is normally made of atoms with ___ valence electrons.

• A. Four to eight
• B. One to three
• C. Zero
• D. Four to six

Answer: (B)

Valence electrons determine how easily electrons can move through a material. Conductors have outer electrons that are loosely bound and can drift under an electric field. In metals, these valence electrons aren’t tied to any single atom but form a mobile “sea” that carries current. Atoms in conductors typically have only a small number of valence electrons, usually one, two, or three, which makes it easy for electrons to become part of the current. If an atom has four or more valence electrons, those electrons are held more tightly, so the material tends to resist electron flow and behave more like an insulator. Atoms with zero valence electrons wouldn’t provide electrons readily able to participate in conduction. So, one to three valence electrons best describes common conductors.