Editing Soap (section)

===Toilet soaps===
[[File:Micelle.svg|thumb|upright=1|Structure of a [[micelle]], a cell-like structure formed by the aggregation of soap subunits (such as [[sodium stearate]]): The exterior of the micelle is hydrophilic (attracted to water) and the interior is lipophilic (attracted to oils).]]
In a domestic setting, "soap" usually refers to what is technically called a toilet soap, used for household and personal cleaning. Toilet soaps are salts of fatty acids with the general formula ([[Carboxylate ion|RCO<sub>2</sub><sup>−</sup>]])M<sup>+</sup>, where M is [[Sodium|Na]] (sodium) or [[Potassium|K]] (potassium).<ref name=UllSoap/>

When used for cleaning, soap [[solubilize]]s particles and grime, which can then be separated from the article being cleaned. The insoluble oil/fat "dirt" become associated inside [[micelle]]s, tiny spheres formed from soap molecules with polar [[hydrophile|hydrophilic]] (water-attracting) groups on the outside and encasing a [[lipophilicity|lipophilic]] (fat-attracting) pocket, which shields the oil/fat molecules from the water, making them soluble. Anything that is soluble will be washed away with the water. In [[hand washing]], as a surfactant, when lathered with a little water, soap kills [[microorganism]]s by disorganizing their membrane [[lipid bilayer]] and [[Denaturation (biochemistry)|denaturing]] their [[protein]]s.{{Citation needed|date=September 2023}} It also [[emulsifies]] oils, enabling them to be carried away by running water.<ref>{{Cite web|url=http://cool.conservation-us.org/waac/wn/wn23/wn23-3/wn23-304.html|title=A Brief History of Aluminum Stearate as a Component of Paint|last=Tumosa|first=Charles S.|date=2001-09-01|website=cool.conservation-us.org|language=en|access-date=2017-04-05|url-status=live|archive-url=https://web.archive.org/web/20170318085239/http://cool.conservation-us.org/waac/wn/wn23/wn23-3/wn23-304.html|archive-date=2017-03-18}}</ref>

When used in [[hard water]], soap does not lather well but forms [[soap scum]] (related to [[metallic soap]]s, see below).<ref>{{cite book |last1=Holman |first1=John S. |last2=Stone |first2=Phil |title=Chemistry |url=https://books.google.com/books?id=j9auT6Jd_JMC&pg=PA174 |publisher=Nelson Thornes |date=2001 |page=174 |isbn=9780748762392}}</ref>