What Distinguishes a Metal From a Nonmetal?

By Staff WriterLast Updated Mar 28, 2020 4:02:39 PM ET
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In general, metals, unlike nonmetals, are good conductors of heat and electricity, malleable, ductile, and almost always solid at room temperature. Metals very often have only between one and three electrons in their outer valence shells, while nonmetals typically have between four and eight. Metals tend to have a metallic lustre and are opaque as thin sheets, while nonmetallic solids tend to have dull surfaces and are transparent.