everyday chemistry - Why does bleach feel slippery?

My high-school chemistry teacher taught us the mantra "bases are slippery-soapy-slimy!"

This question and this answer in Quora say this is due to saponification - conversion of lipids from the top layer dead skin cells into a soap-like substance.

During some household cleaning I ended up with a small amount of a fairly strong solution of bleach in water between my thumb and forefinger and noticed it felt quite slippery, and it took several seconds of rubbing under water for it to stop.

In this case I would guess that saponification is not the explanation for the very slippery feeling. Is there another explanation?

Answer

• Maybe it needs to be clarified that the salt of a strong base and a weak acid can conduct saponification. Therefore the fact that bleach reacts with fatty acids creating soap, does not necessarily mean that bleach should be all just base (nor that something else other than saponification should be happening).

Household bleach is mainly sodium hypochlorite ($\ce{NaClO}$) dissolved in water (~<5%). One reason it works as a disinfectant is that it reacts with fatty acids of living organisms' membrane and turns them into soap.

$$\ce{NaClO (bleach) + R-COOH (fatty acid) → HClO + R-COONa (soap)}$$

(There are other mechanisms by which hypochlorite is known to perform disinfection, though the focus of this answer is to address how the slippery feeling comes about)

• Why is soap slippery

The non-polar side of the soap molecule is less interactive with solid surfaces than polar substances such as water. Therefore soapy water flows with less friction on solid surfaces compared to water and is more slippery.