Why does “pure” alcohol feel so strange to the touch?

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I had to clean out some PC junk recently and I used a tupperware container filled to the brim with 99% isopropyl alcohol to get the gunk out.

I dipped my hands in to get the parts out and I noticed that the alcohol felt very weird in my hands. I don’t know quite how to describe it, but it felt very strange compared to water. Not as much resistance, and it felt very weird on my skin. Almost as if there was no friction against my skin.

What’s the cause of this? Is it surface tension? Maybe a weird chemical reaction with my skin that makes it feel that way?

I googled this and only got results about treating open wounds with alcohol.

In: Chemistry

Hard to know about a “strange feeling”. Maybe this: alcohol dissolves your natural skin oils, leaving them feeling unusually clean.

Isopropyl alcohol (C3H7OH) *looks* like water (H2O) but molecularly it’s more similar to oil (Various CH complexes) and has slightly “oily” behavior – it has less internal surface tension and doesn’t wet surfaces as aggressively as water does.

It also readily evaporates at body temperature and is moderately soluble in fats – you may have noticed your hands got very cold and dry as it wicked the skin oils away.

It evaporates very quickly taking energy from Its surroundings, therefore feeling very cold. Also dissolves fat from your skin, making it dry.

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Alcohol is both soluble in water and in oil, since it has both a charged and a lipid end.

However, there are loads of chemicals with this property.

What is in fact strange is how water behaves. Not many liquids have the same properties as water. If anything, that is the strange feeling.

Short answer: there aren’t all that many liquids that you come in contact with frequently. Most of them are water-based. Water with stuff in it.

Alcohol is fundamentally different. It’s not alcohol in water, it’s that the alcohol IS the liquid. Most of us have water as our frame of reference for what we expect a liquid to be like, but alcohol is as different from water as oil or dish soap is.

99% alcohol really wants to form an azeotrope with water, so will actually pull water from the cells in your skin in order to dilute to a 91% concentration

Other fun fact: doing this with lye (and sometimes bleach) feels super smooth because you now have a liquid layer of dissolved skin between your fingers.