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Comment by gilleain | Hacker News Reader

As another interesting semi-related topic, what about https://en.wikipedia.org/wiki/Superacid - they are super!

Also one of them is magic! https://en.wikipedia.org/wiki/Magic_acid :)

I was just remembering these while playing with my pool chemistry. Had the fleeting memory of negative pHs too -- always fun when a maxim you're taught in early education (pH scale is from 0 - 14) is later given a few exceptions.

https://www.thoughtco.com/is-a-negative-ph-possible-603653

Well, negative pH is mathematically impossible, given that pH is the -log of the hydrogen ion concentration. It makes no physical sense to discuss "negative hydrogen ion concentration". If anything, it's mostly a shorthand than an actual phenomenon.

Check this out https://chemistry.stackexchange.com/questions/5737/is-a-nega...

If you go one step further than the simple math formula - pH isn't just describing the concentration of hydrogen ions in a solution but rather that solution's ability to donate/accept H+ ions. So a solution of strong acid which is inhibited to fully dissociate into H+ and it's anion would have a pH much lower than the measured value in the solution. As H+ ions are donated, the acid in solution further dissociates providing more H+ ions, so clearly the solution is more acidic than originally measured.

This is how mine water and volcanic hot springs end up with negative pH; https://core.ac.uk/download/pdf/17247528.pdf

My first ever lecture was on magic acid in 2012! Ha. Introductory inorganic chemistry

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