What is the chemical equation of soap?

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Assume humorous intentions.
Supporting Member
Sep 20, 2021
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Hi friends!

I went down a Google deep-dive/ rabbit hole! I also fell down a SMF rabbit hole trying to dig myself out of the first one, and it's been a LONG time since HS chemistry!

"oil" + NaOH (or KOH for people who are not me) = "soap" but what are those formulas? Does it change depending on the oils you use? Below are the most helpful things I've found, which might explain why I'm so lost!

I'm hoping someone, much smarter than I, could explain it?

It's this little voice in my mind that keeps bugging me about it.

Thanks so much!



Below is from Chemicals in Liquid Soap | Brenntag:

"What is the formula for soap
For centuries, humans have known the basic recipe for soap — it is a reaction between fats and a strong base. The exact chemical formula is C17H35COO- plus a metal cation, either Na+ or K+. The final molecule is called sodium stearate and is a type of salt. Depending on the metal cation, soaps are either potassium salts or sodium salts arranged as long-chain carboxylic acids.
Typically, the formation of these chains involves combining potassium hydroxide with an animal or vegetable fat, or sometimes with acetic acid. A soap molecule does two things — it bonds to both water and debris. That is due to its hydrophilic, or "water-loving," and hydrophobic, or "water-fearing," components. A molecule of soap has a hydrophilic anionic "head" and a hydrophobic "tail" made of hydrocarbons. The head of the molecules is attracted and dissolves in water, while the hydrocarbon tail is attracted to dirt and grease, and repelled by water.

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