Hydrogen Isotopes

 

Source: https://xkcd.com/2719/

See, it's funny because hydrogen actually does have three isotopes with official names: protium (hydrogen-1), deuterium (hydrogen-2), and tritium (hydrogen-3).

If you're not ready to follow along, the empty circles with a + are protons. Each hydrogen by definition has to have one of those, so a couple of the isotopes up there aren't really hydrogen.

The filled, black circles are neutrons. Those can be different - which is what makes isotopes different in the real, non-xkcd world.

The smaller circles with a minus sign (-) are electrons. Most neutral hydrogens have one of those, too, because positives and negatives sort of need to balance each other out.

The rest of them in that diagram aren't real. Technically explainxkcd.com says ium and instant hydrogen technically exist but certainly aren't common. The oops, all neutrons is a reference it Cap'n Crunch's Oops, all berries cereal. I would reference a particular comedian's routine about the Oops, all berries cereal, but it's not school-appropriate. 

His name is K. Trevor Wilson...in case you wanted to look it up...which you clearly shouldn't do because he uses words that aren't school-appropriate. 

$500,000 of Calcium - Periodic Table of Videos

I think it's necessary to watch the below video first to understand the above video.

Take a couple of minutes. I'll wait.



It's the moment at 2:50 where they mention at the "cost of the calcium they consume is 10% of the operation costs of the machine" that got me.

That and the fact that Yuri Oganessian is there...talking. He's only the second person to have had an element named after himself while he was alive and the only person currently alive to have that happen.

He is among the greatest chemistry (or physicists) alive.

Back to the calcium, though. I initially wondered about why the calcium would be so amazingly expensive, thinking maybe it had to do with simple purification to make sure there weren't any non-calcium contaminants. But I hadn't thought about the need to only use heavy isotopes of calcium - specifically calcium-48 - for the nuclear synthesis. Purifying calcium's mixture of calcium isotopes into just calcium-48 (0.187% of all calcium atoms according to wikipedia and confirmed by webelements) is apparently tough...and expensive.

I especially appreciate that the Professor mentions (at 1:40 in the top video) that his shaky hands prevent him from even touching the vial of calcium-48 carbonate.