Defining Nonmetals
Nonmetals are a group of chemical elements that generally lack the typical metallic properties such as malleability, ductility, and high electrical conductivity. They are found on the right side of the periodic table, playing critical roles in biological and environmental systems. Unlike metals, nonmetals tend to gain or share electrons in chemical reactions.
Key Characteristics and Properties
Nonmetals typically exhibit high ionization energies and high electronegativity, meaning they readily attract electrons to form negative ions (anions) or share electrons to form covalent bonds. Physically, they often appear as gases (e.g., oxygen, nitrogen), liquids (e.g., bromine), or dull, brittle solids (e.g., carbon, sulfur) at room temperature. They are poor conductors of heat and electricity, serving as insulators in many applications.
Examples and Periodic Table Placement
Common examples of nonmetals include hydrogen (H), carbon (C), nitrogen (N), oxygen (O), phosphorus (P), sulfur (S), and all elements in the halogen (Group 17) and noble gas (Group 18) families. On the periodic table, nonmetals are located on the upper right-hand side, separated from the metals by a zigzag line of metalloids, which exhibit properties intermediate between metals and nonmetals.
Importance in Science and Industry
Nonmetals are fundamental to life and countless industrial processes. Oxygen is indispensable for respiration, nitrogen is a crucial component of proteins and nucleic acids (like DNA), and carbon forms the backbone of all organic molecules. Industrially, nonmetals like chlorine are used for water purification, while noble gases such as neon are used in lighting, highlighting their diverse and essential applications.