Chemical substance In organic chemistry, there can be more than one chemical compound with the same composition and molecular weight. Generally, these are called isomers. Isomers usually have substantially different chemical properties, and often may be isolated without spontaneously interconverting. A common example is glucose vs. fructose. The former is an aldehyde, the latter is a ketone. Their interconversion requires either enzymatic or acid-base catalysis. However, tautomers are an exception: the isomerization occurs spontaneously in ordinary conditions, such that a pure substance cannot be isolated into its tautomers, even if these can be identified spectroscopically or even isolated in special conditions. A
Systematic name with or without numerical prefixes; e.g. pentane, oxazole." However, when trivial names have become part of chemical nomenclature, they can be the systematic name of a substance or part of it. Examples for some systematic names that have trivial origins are benzene (cyclohexatriene) or glycerol (trihydroxypropane). There are standardized systematic or semi-systematic names for: Systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial name is a name