nonmetallic

Nonmetallic refers to substances that do not possess typical metallic properties. In chemistry, nonmetals are elements and compounds that generally have low electrical and thermal conductivity, lack a metallic luster, and are often brittle in the solid state, though there are notable exceptions. They form a wide range of substances, from simple elements to complex compounds, and their chemical behavior is often dominated by covalent bonding.

In the periodic table, common nonmetals include hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, the halogens, and the noble gases. Metalloids such as boron and silicon lie between metals and nonmetals and are not classified as nonmetals themselves. Nonmetals exist as gases (for example, nitrogen and oxygen), liquids (bromine), and solids (carbon, sulfur, phosphorus) at room temperature.

Nonmetallic materials underpin many everyday products and industries. Ceramics, glass, cement, and plastics are valued for insulating properties, chemical resistance, and versatility. Carbon-based materials, including graphite and various polymers, play crucial roles in electronics, construction, and packaging. Nonmetallic minerals—such as silica (quartz), limestone, gypsum, clays, and phosphate rock—are widely used in construction, agriculture, and industry, and they contrast with metallic minerals that contain metallic elements.

Overall, nonmetallic properties define a broad category of substances and materials with applications spanning science, manufacturing, and consumer goods.