Chemical compound


A chemical compound is a chemical substance of two or more different chemically bonded chemical elements, with a fixed ratio determining the composition. The ratio of each element is usually expressed by chemical formula. For example, water (H<sub>2</sub>O) is a compound consisting of two hydrogen atoms bonded to an oxygen atom. The atoms within a compound can be held together by a variety of interactions, ranging from covalent bonds to electrostatic forces in ionic bonds. A continuum of bond polarities exist between the purely covalent bond (as in H<sub>2</sub>) and ionic bonds. For example H<sub>2</sub>O is held together by polar covalent bonds. Sodium chloride is an example of an ionic compound.