# the amazing power of soap

**URL:** <https://boards.straightdope.com/t/the-amazing-power-of-soap/128066>\
**Category:** Factual Questions\
**Created:** [September 12, 2002, 1:47am UTC](https://boards.straightdope.com/t/the-amazing-power-of-soap/128066 "2002-09-12T01:47:13Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![jb\_farley](https://avatars.discourse-cdn.com/v4/letter/j/9d8465/32.png) [@jb\_farley](https://boards.straightdope.com/u/jb_farley)\
**Post date:** [September 12, 2002, 1:47am UTC](https://boards.straightdope.com/t/the-amazing-power-of-soap/128066/1 "2002-09-12T01:47:13Z")

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i was washing dishes yesterday, and stopped and stared for a while at the bubblse of grease that popped up to the surface of the dishwater. they were slowly decomposed by the soap.

and i got to thinking. is there a release of energy when soap reacts with grease and water?

is the hydrophobic-bonding-to-hydrophobic-bonding-to-hydrophilic a chemical reaction, or a physical reaction?

jb

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**Author:** ![lel](https://avatars.discourse-cdn.com/v4/letter/l/8797f3/32.png) [@lel](https://boards.straightdope.com/u/lel)\
**Post date:** [September 12, 2002, 4:45am UTC](https://boards.straightdope.com/t/the-amazing-power-of-soap/128066/2 "2002-09-12T04:45:10Z")

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Well, Cecil does talk, albeit generically, about how [soap](http://www.straightdope.com/classics/a2_398.html) works. I don’t know if this is precise enough to be of any help, however.

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**Author:** ![Rhapsody](https://avatars.discourse-cdn.com/v4/letter/r/9de0a6/32.png) [@Rhapsody](https://boards.straightdope.com/u/Rhapsody)\
**Post date:** [September 12, 2002, 5:13am UTC](https://boards.straightdope.com/t/the-amazing-power-of-soap/128066/3 "2002-09-12T05:13:26Z")

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soap works primarily by reducing surface tension of water allowing it to absorb better and mix with dirt/grease etc.

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**Author:** ![Dr.Lao](https://avatars.discourse-cdn.com/v4/letter/d/2bfe46/32.png) [@Dr.Lao](https://boards.straightdope.com/u/Dr.Lao)\
**Post date:** [September 12, 2002, 5:25am UTC](https://boards.straightdope.com/t/the-amazing-power-of-soap/128066/4 "2002-09-12T05:25:53Z")

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> [@](#):
>
> \*Originally posted by Rhapsody \*  
> \*\*soap works primarily by reducing surface tension of water allowing it to absorb better and mix with dirt/grease etc. \*\*

But that is not **jb\_farley** is observing. The grease bubble is being dissolved by the formation of micelle.

It is a physical reaction, not chemical. It could be endothermic or exothermic. I can’t think of a good way to tell which it would be.