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.
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.
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.
Chemistry student are also prolific pirates, any chemistry text you could want is typically available on the web in a PDF format. My personal favourite, Wade's Organic Chemistry 8th Edition, is easily findable on Google.
Reminds me of one of the childhood book titles that I inexplicably remember even as I forget things from last week - "Acids, Bases and the Chemistry of the Covalent Bond". Which [1] tells me was written by Calvin A. VanderWerf, University of Kansas.
Even more interesting is how some chemicals (like water or amino acids) are amphoteric and act as both acids and bases, depending on what environment they are in.
Gas phase Brønsted acids are kind of mind boggling, if I'm understanding them correctly. They are up to 10^(30) times more acidic than standard strong acids. The goal (I'm not sure if this has been reached) is a compound that in equilibrium has free protons, just bouncing around in space. (In solution, the free protons are always bound to something, for example H3O+ in water.)
People informed on Chemistry usually take "acid = you'll get H₃O⁺ in water" and "base = you'll get OH⁻ in water"; that is, the Arrhenius' definition, updated for modern times. Brønsted-Lewis actually makes you think about what's going on (the transference of H⁺), in order to generalise it to other situations.
For example, consider the following reaction:
H₂O + HF ←→ OH⁻ + H₂F⁺
You don't get H₃O⁺ so by Arrhenius' [updated] definition there wouldn't be an acid there. But there is one - H₂O.
And someone might say "but wait, Arrhenius talks about H⁺!" - well, go look for "bare" protons in nuclear fusion, not in chemical reactions.
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[ 3.7 ms ] story [ 42.2 ms ] threadAlso one of them is magic! https://en.wikipedia.org/wiki/Magic_acid :)
https://www.thoughtco.com/is-a-negative-ph-possible-603653
This is how mine water and volcanic hot springs end up with negative pH; https://core.ac.uk/download/pdf/17247528.pdf
https://flexbooks.ck12.org/cbook/ck-12-chemistry-flexbook-2....
Would be a more accessible document for the audience.
[1] https://pubs.acs.org/doi/10.1021/ed039p273.2
People informed on Chemistry usually take "acid = you'll get H₃O⁺ in water" and "base = you'll get OH⁻ in water"; that is, the Arrhenius' definition, updated for modern times. Brønsted-Lewis actually makes you think about what's going on (the transference of H⁺), in order to generalise it to other situations.
For example, consider the following reaction:
H₂O + HF ←→ OH⁻ + H₂F⁺
You don't get H₃O⁺ so by Arrhenius' [updated] definition there wouldn't be an acid there. But there is one - H₂O.
And someone might say "but wait, Arrhenius talks about H⁺!" - well, go look for "bare" protons in nuclear fusion, not in chemical reactions.