Nonmetals usually have no luster and are dull in appearance. Nonmetals do not conduct heat and electricity well. Nonmetals are brittle and thus break easily. They cannot be drawn out into wire or hammered into thin sheets. In other words, nonmetals are neither ductile nor malleable. Nonmetals usually have lower densities and lower melting points than metals.

Nonmetals are not as easy to recognize as a group as are metals. Nonmetals can be noticeably different from one another. For example, bromine is a brown liquid, oxygen is a colorless gas, and sulfur is a yellow solid. Yet all are nonmetals.