this post was submitted on 28 Jan 2026
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xkcd #3200: Chemical Formula

Title text:

Some of the atoms in the molecule are very weakly bound.

Transcript:

Transcript will show once it’s been added to explainxkcd.com

Source: https://xkcd.com/3200/

explainxkcd for #3200

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[–] stelelor@lemmy.ca 22 points 1 month ago (3 children)

The formula starts with CH, which means the universe is organic.

[–] PumpkinSkink@lemmy.world 4 points 1 month ago (1 children)

I mean... there's a C-H bond in there somewhere.

[–] ranzispa@mander.xyz 3 points 1 month ago

Pretty sure that yes, somewhere in the universe there is organic matter.

[–] djehuti@programming.dev 2 points 1 month ago

Indeed! Hello!

[–] AnarchoEngineer@lemmy.dbzer0.com 15 points 1 month ago

I’m not a physicist, but even if Astatine is being produced in minute quantities by decay, a half life of 8hrs should probably put it lower on the numbers than Americium.

Americium is produced anywhere you have lots of free neutrons. This may be rare on earth outside of nuclear power plants and bomb test sites, but not necessarily rare in the universe. Especially since it has a half life of 432years, so unlike astatine it can actually accumulate a bit and not just decay immediately.

Astatine basically doesn’t exist. The total amount in the entirety of earth’s crust at any given time is estimated to be less than a gram.

So I feel like the amounts should be flipped or at the very least closer in orders of magnitude.

[–] palordrolap@fedia.io 14 points 1 month ago (5 children)

There are exotic atoms in that chemical formula that aren't in the periodic table. Not even if you count the equivalent table of potential antimatter atoms.

Muonium is sure to exist in non-zero quantities at any one time, for example.

[–] Pyro@programming.dev 12 points 1 month ago (1 children)
[–] fruitycoder@sh.itjust.works 2 points 1 month ago

This made me laugh too much

[–] WR5@lemmy.world 4 points 1 month ago* (last edited 1 month ago)

"Approximate chemical formula"

[–] kopasz7@sh.itjust.works 2 points 1 month ago (1 children)

Still can't find blackholium, what element number is it?

[–] Trail@lemmy.world 2 points 1 month ago (2 children)
[–] palordrolap@fedia.io 3 points 1 month ago (1 children)

-1 would be antihydrogen. Blackholium is whatever number is large enough to cause gravitational collapse, so probably one or two more than the largest neutron star.

[–] Trail@lemmy.world 1 points 1 month ago

Yeah I was more like referring to an overflow or something.

[–] ElBarto@piefed.social 1 points 1 month ago
[–] nialv7@lemmy.world 1 points 1 month ago

And neutron stars.

[–] gegil@sopuli.xyz 1 points 1 month ago

What about elements beyond 119?

[–] GreatRam@lemmy.world 3 points 1 month ago

Gold and silver are nice

[–] humanspiral@lemmy.ca 2 points 1 month ago (1 children)

surprised there's so much gold.

[–] ryannathans@aussie.zone 2 points 1 month ago

Neutron stars go brrr