Formula unit Formula unit A formula unit in chemistry is the empirical formula of any ionic or covalent network solid compound used as an independent entity for stoichiometric calculations. It is the lowest whole number ratio of ions represented in an ionic compound. Examples include ionic NaCl and KO and covalent networks such as SiO and C (as diamond or graphite). Ionic compounds do not exist as individual molecules; a formula unit thus indicates the lowest reduced ratio of ions in the compound. A "chemical formula" shows the kinds and numbers of atoms in the smallest representative unit of a substance. In
Composition of matter may be produced by mechanical or chemical operations, and its result may be a compound substance resolvable into its constituent elements by mechanical processes, or a new substance which can be destroyed only by chemical analysis. A newly synthesized chemical compound or molecule may be patented as a composition of matter. Patents have been allowed on transitory products, such as short-lived chemical intermediates. In "Diamond v. Chakrabarty", the United States Supreme Court held that a genetically-altered living microorganism was patent-eligible subject matter. The "Chakrabarty" Court said that "we must determine whether respondent's micro-organism constitutes a 'manufacture' or 'composition of matter'