Questions tagged [soap]
Soap is a salt of fatty acid used generally for cleansing purposes. For questions relating to soap or saponification.
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Quantifying soapiness; there's pH, pKa and pO2, is there a p_soap or p_surfactance?
Yes, $\mathrm{pH}$ is a concentration, $\mathrm{p}K_\mathrm{a}$ is a dissociation constant, and $\mathrm{pO_2}$ is a partial pressure. These are (roughly speaking) ways to indicate how much of a key ...
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Does hand dishwashing liquid degrease as well as add "grease"?
When preparing a copper etching plate for etching, it must be degreased completely before putting on the etching ground. Otherwise the acid may "bite" through the ground ("foul biting&...
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Soap equation using potash
I'm trying to understand the chemical formula of soap using potash ($\ce{K2CO3}$) as they did in antiquity instead of using sodium hydroxide ($\ce{NaOH}$) or potassium hydroxide ($\ce{KOH}$). I've ...
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Substituting K2CO3 for KOH in Soap [duplicate]
Wood water obtained by running water through hardwood ashes has a high quantity of $\ce{K2CO3}$, historicaly this was called lye. Yet soap recipes today seem to use $\ce{KOH}$ or $\ce{NaOH}$ as lye.
$...
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How do I remove some of the glycerin when making soap?
In some older descriptions of soap making, I read that when the base is added to the fat the glycerin separates and collects at the top where it is drained off. Fine, but there are no details.
In ...
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The cleansing action of soap
My textbook says that:
The formation of micelles takes place only above a particular
temperature called Kraft temperature (Tk ) and above a particular
concentration called critical micelle ...
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Three Phases in TFM test instead of two
I am currently trying to perform the Total Fatty Matter (TFM) test on soap and for some reason I am getting three phases instead of two.
The surfactant used is SLES and other reagents include hot ...
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What is the chemical formula(s) for liquid potassium-based soap? [closed]
Many places say that liquid soap is generally potassium-based, while the solid stuff is sodium-based.
But, while I have found several sites saying that solid soap is usually sodium stearate, I can't ...
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Where do the chloride ions go during saponification precipitation?
During saponification hydroxide ions from the lye join to the triglyceride to form glycerol, and the sodium bonds with the fatty acids making the soap molecules. However, it is sometimes the case that ...
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How does a dry shampoo work?
From my chemistry knowledge, I know that soaps are made from fatty acids and some sort of base and this reaction also gives us $\ce{H_2O}$ so the grease in hair dissolves and gets washed away in water....
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What caused a colour change when I mixed two different dish soaps?
I recently purchased "organic" dish soap refill made from saponified coconut oil and potassium soap (full ingredient list). Instead of waiting for the old dish soap (Dawn) to be completely ...
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Reason for three phases in total fatty matter test on soap [duplicate]
I am currently trying to perform the Total Fatty Matter (TFM) test on soap and for some reason I am getting three phases instead of two.
The surfactant used is SLES and other reagents include hot ...
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How can a detergent "designed for sensitive skin" warrant the "corrosive" hazard symbol?
The dish-washing detergent, which you can find an image of here, has the following hazard symbol on its back:
On the back, it additionally says that if it comes in contact with the skin, you should ...
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How to remove the water from soap
I find when making soap that a difficult part is removing the water.
Currently what I do is melt the soap and then put the melted soap into a vacuum chamber. This draws the water out by vacuum. You ...
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Why can't we make liquid crystal displays out of soap?
Liquid Crystal Displays (LCDs) are widely used everywhere, especially in the screens of computer monitors, TVs, and small devices like thermostats. As its name suggests, LCDs use substances with ...
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Cheap way to mix satured fat (beef tallow) with water?
I want to mix beef tallow (satured fat) in water. I want to prepare food or edible product.
I know I must use a emulsifier, but I seen in this video, I can do it by a vacuum chamber.
That means I have ...
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Saponification - Oil and Alcohol?
I've been reading that a saponification reaction typically involves NaOH or KOH. I was wondering - could anything that contains an OH group cause a saponification reaction? For instance, coconut oil + ...
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Is Sodium Laurate (SL) the same as Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES)? [closed]
Is Sodium Laurate (SL) the same as Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES)?
There's controversy surrounding using SLS and SLES ingredients due to possible carcinogens. However, ...
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How does soap help in cleaning clothes and rinsing off oil and grease?
When we say that we agitate clothes so that grease particles get separate out from clothes as ionic part of hydrocarbon chains of soap is attached to water and non polar part of chain is dissolved in ...
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Which part of a soap molecule is the hydrophilic part? [closed]
Is the hydrophilic part of the soap both the cation ($\ce{Na+/K+}$), just the $\ce{COO-}$, or both of those sections together like the picture shown below? Do the cation and the anion dissociate from ...
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