Slippery Properties of Soap, Oil, NaOH, Bleach

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In summary, sodium hydroxide (NaOH) solution, bleach (active ingredient: sodium hypochlorite), soap, and oils all share the property of being slippery to the touch. This is due to low intermolecular forces resulting in low shear forces and the ability to fill in the "valleys" of a surface, similar to how a lubricant works. Additionally, their basic nature allows for reactions with skin oils, such as saponification, which results in a soapy layer on the skin. This is also why bleach, with its basic pH, can have the same effect.
  • #1
Ouabache
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I have noticed that (sodium hydroxide) NaOH solution and also bleach (active ingredient: sodium hypochlorite), soap and oils are all slippery to the touch.. Why is that so? What propertie do they share that allow them to behave this way?
 
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  • #2
I would imagine low intermolecular forces resulting in low shear forces, and they fill in the 'valleys' of a surface. Basically that's how a lubricant works.
 
  • #3
Anything that is basic is usually slippery
 
  • #4
NaOH basically turns some of your skin cells into soap through a saponification reaction. I'm not sure about other bases though.
 
  • #5
Cesium said:
NaOH basically turns some of your skin cells into soap through a saponification reaction. I'm not sure about other bases though.
Ya, I was going to say, it could be due to the NaOH (or more specifically, the OH- ?) reacting with the oils/fats in your skin making a thin layer of soap which gives it the slippery texture.
 
  • #6
Thanks for all you ideas; the low intermolecular forces (for why oils or lubricants are slick) and also the saponification of base with skin oils.. I suspect that is what happens with bleach too (NaOCl) although its pH is not as high as sodium hydroxide.. It is still basic (ph = 9-10) and may be enough to enable the reaction.
 
  • #7
Yeah, NaOH solutions do feel slippery, I noticed that too. I suggest keeping your hands out of them.
 
  • #8
I think it is the Na+ that is specifically relevant to the soapy feeling (and the basic medium). The "soap" is after all the sodium salt of the fatty acid (of course, another alkali, K+ say, would do this too). That's probably why the same thing happens with bleach.
 
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FAQ: Slippery Properties of Soap, Oil, NaOH, Bleach

What makes soap slippery?

Soap gets its slippery properties from its ability to reduce surface tension of water. This allows it to form a layer between the skin and water, making it easier to wash away dirt and oils.

Why do oil and soap have similar slippery properties?

Oil and soap both have hydrophobic (water-repelling) properties, which allows them to easily slide over surfaces. This is why they both feel slippery and can be used to lubricate surfaces.

How does the presence of NaOH affect the slipperiness of soap?

Sodium hydroxide (NaOH) is a key ingredient in soap-making because it reacts with fats and oils to create soap molecules. These soap molecules have both hydrophobic and hydrophilic properties, making them effective at reducing surface tension and creating a slippery feel.

Can bleach also be slippery like soap and oil?

No, bleach does not have the same slippery properties as soap and oil. Bleach is a strong chemical that is used for disinfecting and stain removal, but it does not have the same lubricating properties as soap and oil.

How can I make my soap or oil less slippery?

To reduce the slipperiness of soap or oil, you can add substances that absorb or counteract their lubricating properties. For example, cornstarch can be added to oil to make it less slippery, and salt can be added to soap to decrease its slip. However, keep in mind that these additions may also affect the effectiveness of the soap or oil for its intended purpose.

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