Oh, a related story that I tell: there is a graph in the Jurassic Park book that is completely LOL for anyone who has made a histogram from real data. Crichton liked to pretend he knew science, but actually doing it makes a difference.

A short science lesson. The histogram of murders vs year in Springfield is indistinguishable from random noise. Any interpretation of this data is the equivalent of seeing a dog in the clouds. For comparison, the graphs I show below are based on a random-number generator.

There is no hope for humanity.

Schrödinger's cat RPMD for tunneling through a 0.2 kcal/mol barrier at 10 K, forming the anti-Markovnikov product from BH3 + propene. The part that freaks me is how long tunneling takes, literally hundreds of fs with the H spread out on both sides of the barrier.

It would take 10 TAs and a classroom with tables that automatically groups people.

Those are indeed words there, but if “natural” includes everything humans do, despite its #1 dictionary definition, then the word has no meaning at all. But I suppose Humpty Dumpty apply:

You should verify my math and attempt to pick holes in it. But I love the word "useful." For thermodynamics, an activity of 1 for pure water making its pKa 14 is most useful. But here is a different question. For dilute MeOH (pKa 15.5) and dilute 18OH2 in water, which is true?

Ok, just for fun, let's depart into la-la land and choose a different equation that would make the pKa of dilute 18OH2 be 14 instead of 15.7. This equation would work:

Since it has been asked about, I thought I should expand slightly on an "assumption" here. I don't see this as an assumption at all - I am just counting - but you might say that I am assuming this:

Start here, a problem I give to grad students.