Editing Soap (section)

{{short description|Substance used for cleaning}}
{{other uses}}
{{pp-semi-indef|small=yes}}
[[File:Handmade soap cropped and simplified.jpg|thumb|upright=1.2|A handmade soap bar]]
[[File:Sodium stearate v2.svg|thumb|upright=1.4|Two equivalent images of the chemical structure of [[sodium stearate]], a typical ingredient found in bar soaps]]
[[File:Action of soap on oil.ogv|thumb|upright=1|[[Emulsion#Emulsifiers|Emulsifying]] action of soap on oil]]

'''Soap''' is a [[salt (chemistry)|salt]] of a [[fatty acid]] (sometimes other carboxylic acids) used for cleaning and lubricating products as well as other applications.<ref>{{GoldBookRef |title=Soap |file=S05721 |accessdate=9 August 2010}}</ref> In a domestic setting, soaps, specifically "toilet soaps", are [[surfactant]]s usually used for [[washing]], [[bathing]], and other types of [[housekeeping]]. In industrial settings, soaps are used as [[thickener]]s, components of some [[lubricant]]s, [[emulsifier]]s, and [[catalyst]]s.

Soaps are often produced by mixing fats and oils with a [[Base (chemistry)|base]].<ref>{{cite web|title=What's The Difference Between Soap and Detergent|publisher=cleancult.com|url=https://www.cleancult.com/blog/whats-the-difference-between-soap-and-detergent/|access-date=2019-12-18|archive-date=2019-12-18|archive-url=https://web.archive.org/web/20191218165118/https://www.cleancult.com/blog/whats-the-difference-between-soap-and-detergent/|url-status=live}}</ref> Humans have used soap for millennia; evidence exists for the production of soap-like materials in ancient [[Babylon]] around 2800 BC.<ref>{{cite book |last=Willcox |first=Michael |title=Poucher's Perfumes, Cosmetics and Soaps |publisher=Kluwer Academic Publishers |year=2000 |isbn=978-0-7514-0479-1 |editor=Hilda Butler |edition=10th |location=Dordrecht |page=453 |chapter=Soap |quote=The earliest recorded evidence of the production of soap-like materials dates back to around 2800 BCE in ancient Babylon. |chapter-url=https://books.google.com/books?id=4HI8dGHgeIQC&pg=PA453 |archive-url=https://web.archive.org/web/20160820150103/https://books.google.com/books?id=4HI8dGHgeIQC&pg=PA453 |archive-date=2016-08-20 |url-status=live}}</ref>