What is Isomer?
[[File:Milchsäure Enantiomere.svg|thumb|[[Lactic acid]] has two isomers]] [[File:D+L-Alanine.gif|thumb|right|200px|[[Alanine]] has two [[isomers]]. They are exactly the same except they are backwards from each other. This sort of isomer is called an '''optical isomer''']] An '''isomer''' in chemistry is a [[chemical compound|chemical]] compound that has the same [[molecular formula]] as another, but it has a different arrangement of [[atoms]] in space. In other words, isomers are compounds with the same molecular formula but different structural formula. Different isomers have different chemical properties (that is, they may look, or smell, or taste different from each other).<ref>{{Cite web|title=Isomer - an overview {{!}} ScienceDirect Topics|url=https://www.sciencedirect.com/topics/earth-and-planetary-sciences/isomer|access-date=2021-04-09|website=www.sciencedirect.com}}</ref><ref>{{Cite web|title=isomerism {{!}} Definition, types, & examples |url=https://www.britannica.com/science/isomerism|access-date=2021-04-09|website=Encyclopedia Britannica|language=en}}</ref> There are two main categories: [[stereoisomer]]s and [[Structural isomer|structural isomers]]. Structural isomers are isomers with the atoms making up the molecule joined together in different ways. Structural isomers can be classified further as [[chain isomer]]s, [[position isomer]]s, [[function group isomer]]s, [[tautomer]]s [[metamer]]s and [[ring chain isomer]]s.<ref>{{Cite web|date=2014-05-22|title=A Brief Guide to Types of Isomerism in Organic Chemistry|url=https://www.compoundchem.com/2014/05/22/typesofisomerism/|access-date=2021-04-09|website=Compound Interest|language=en-GB}}</ref> Stereoisomers have different positions of atoms in space and are much more subtle than structural isomers. See [[enantiomer]] for stereoisomers that are related to each other by a reflection: they are mirror images of each other that are non-superimposable. == References == {{reflist}} {{-}} [[Category:Chemical compounds]] [[Category:Stereochemistry]]