Slippery Properties of Soap, Oil, NaOH, Bleach

[Ouabache]

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?

 

[Astronuc]

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.

 

[gravenewworld]

Anything that is basic is usually slippery

 

[Cesium]

NaOH basically turns some of your skin cells into soap through a saponification reaction. I'm not sure about other bases though.

 

[mrjeffy321]

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.

 

[Ouabache]

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.

 

[Rach3]

Yeah, NaOH solutions do feel slippery, I noticed that too. I suggest keeping your hands out of them.

 

[Gokul43201]

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.