Classify these elements as metals, nonmetals, or semimetals.

Key Concepts

Metals

Metals are elements that typically exhibit high electrical and thermal conductivity, malleability, ductility, and a shiny appearance. They are usually solid at room temperature (except mercury) and tend to lose electrons during chemical reactions, forming positive ions. Common examples include iron, copper, and aluminum.

Nonmetals

Nonmetals are elements that generally lack the properties of metals and are characterized by poor conductivity, brittleness in solid form, and a variety of physical states (solid, liquid, gas) at room temperature. They tend to gain electrons in chemical reactions, forming negative ions. Examples include oxygen, nitrogen, and sulfur.

Semimetals (Metalloids)

Semimetals, or metalloids, are elements that possess properties intermediate between metals and nonmetals. They are typically semiconductors of electricity, making them valuable in electronics. Common semimetals include silicon, germanium, and arsenic, which can exhibit metallic luster but are brittle and can behave as either metals or nonmetals in chemical reactions.