I first made my name (such as it is) in my discipline by developing & (more to the point) popularizing a liquid chromatography system for high resolution separations of complicated oligosaccharides. The system used strong anion exchange chromatography to separate ionized (deprotonated) sugars with "dilute" (relatively speaking) NaOH both to ionize the analytes and as the basic (no pun intended) eluant. In most cases, the final concentration was (is) 0.1 molar NaOH, which is most conveniently made* by dilution of commercially available 50% (18.9 M) NaOH solution.
After the first layer of epidermis dissolves away, skin's pretty resistant to 50% NaOH. Again, it's better wiped off first.
... and boy howdy is 50% NaOH
slimy.
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* I am nothing if not lazy -- and, in seriousness, the "carbonate problem" with NaOH-containing solutions is largely circumvented by using the concentrated liquid reagent. Any sodium carbonate (from atmospheric CO2 will precipate to the bottom of the bottle).