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xkcd #2943: Unsolved Chemistry Problems
(imgs.xkcd.com)
Alt text:
I'm an H⁺ denier, in that I refuse to consider loose protons to be real hydrogen, so I personally believe it stands for 'pretend'.
They told me at school that ‘p’ meant ‘negative log’. So ‘pH’ means ‘the negative log of the concentration of Hydrogen ions in moles/litre’.
pH 1 is 1 x 10^-1^ (strong acid)
pH 7 is 1 x 10^-7^ (neutral)
pH 14 is 1 x 10^-14^ (alkaline)
(Chemistry was a long time ago, though)
You're missing a 4 in the alkaline line
Thank you (4 now added!)