What is Homologous series?
[[File:Methane.Structural formula.V1.svg|thumb|right|150px|{{Center|Methane}}]] [[File:Ethane-flat.png|thumb|right|160px|{{Center|Ethane}}]] In [[chemistry]], a '''homologous series''' is a series of [[chemical compound]]s with the same [[general formula]].<ref>{{cite web |url=http://www.bbc.co.uk/education/guides/zm9hvcw/revision |title=Hydrocarbons and homologous series |website=Bitesize |publisher=BBC |access-date=2 September 2016 |archive-date=4 September 2016 |archive-url=https://web.archive.org/web/20160904063925/http://www.bbc.co.uk/education/guides/zm9hvcw/revision |url-status=dead }}</ref> Usually these compounds vary by a single parameter such as the length of a [[carbon]] chain.<ref>{{cite web |url=http://ibchem.com/IB16/10.13.htm |title=Homologous series |publisher=IB Chemistry Web |access-date=2 September 2016 |archive-date=26 November 2016 |archive-url=https://web.archive.org/web/20161126180622/http://ibchem.com/IB16/10.13.htm |url-status=dead }}</ref> [[Example]]s of such series are the [[Open-chain compound|straight-chained]] [[alkane]]s (paraffins), and some of their [[derivative (chemistry)|derivative]]s (such as the primary [[alcohol]]s, [[aldehyde]]s, and (mono)[[carboxylic acid]]s). Compounds within a homologous series typically have a [[wikt:fixed|fixed]] set of [[functional group]]s that gives them similar [[Chemical property|chemical]] and [[Physical property|physical properties]]. For example, the series of primary straight-chained [[alcohol]]s has an [[hydroxyl]] at the end of the carbon chain. These properties typically change gradually along the series, and the changes can often be explained by small differences in [[Molecule|molecular]] size and [[mass]]. == References == {{reflist}} [[Category:Organic chemistry]] {{chem-stub}}