Slippery Properties of Soap, Oil, NaOH, Bleach

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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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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.
 
Anything that is basic is usually slippery
 
NaOH basically turns some of your skin cells into soap through a saponification reaction. I'm not sure about other bases though.
 
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.
 
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.
 
Yeah, NaOH solutions do feel slippery, I noticed that too. I suggest keeping your hands out of them.
 
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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