this post was submitted on 09 Apr 2025
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submitted 4 days ago by [email protected] to c/[email protected]
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[–] [email protected] 20 points 4 days ago (3 children)

How much more energy would you get if you fused uranium?

[–] [email protected] 73 points 4 days ago

Using the rule of thumb, anything heavier than iron requires energy input to fuse. So you lose energy fusing uranium.

[–] [email protected] 31 points 4 days ago* (last edited 4 days ago)

Serious answer: A huge negative amount. Anything above iron requires energy to fuse (which is why it produces energy from fission.) and I'm pretty sure nothing with 184 protons could be stable enough to count as being produced - the nuclei would be more smashed apart than merging at that point.

[–] [email protected] -5 points 4 days ago* (last edited 4 days ago) (2 children)

Ask Hiroshima and Nagasaki.

In alphabetical order.

Edit: oops, those are fission, my bad

[–] [email protected] 16 points 4 days ago (4 children)

Those are fission. Fusion bombs don't fuse uranium. They use a fission bomb to fuse Lithium.

[–] [email protected] 11 points 4 days ago (2 children)

Fusion bombs use a fission bomb to fuse Hydrogen, which is why they're called H-bombs.

[–] [email protected] 11 points 4 days ago

Look at all these nuclear scientists on Lemmy.

[–] [email protected] 7 points 4 days ago (2 children)

Sorry I meant Lithium Deuteride.

6Li2H

https://en.m.wikipedia.org/wiki/Thermonuclear_weapon

[–] [email protected] 6 points 4 days ago (1 children)

I mean if we really want to be technically accurate here, the lithium is just a moderater for the hydrogen isotopes to fuse.

But for me it gets fuzzy when looking at the reaction.

LiD is 4 protons, 8 neutrons. Add a new neutron, and bam, you have 4 protons and 9 neutrons. But that's where it gets weird to me. The lithium needs to decay or something into a tritium and dueterium which forces the tritium to fuse with the existing dueterium in the LiD molecule? Clearly the neutron has enough energy to transfer into one of the atoms to increase the chance of tunneling actually occuring.

[–] [email protected] 4 points 3 days ago (1 children)

The only real purpose of the lithium deuteride is that it's a dry, shelf-stable, room-temperature fuel. The very first hydrogen "bomb" (actually a building-sized device) used supercooled liquid hydrogen as the fusion fuel, but this was obviously not practical for a deliverable bomb.

[–] [email protected] 1 points 3 days ago* (last edited 3 days ago)

I get that part, it's still the reaction I can't wrap my head around mainly because I don't understand how chemistry is any different than alchemy.

I know that lithium itself doesnt fuse to create He+T+D, and I know it can't undergo fission. Since lithium isn't left over, and lithium-6 and 7 are stable, does that mean the neutron with extremely high kinetic energy really knocks like two of the LiD mokecules into each other, causing dueterium -dueterium fusion resulting in He4, and the Li6 gets more neutrons that for it to be come unstable enough to decay into tritium or deuterium?

[–] [email protected] 1 points 4 days ago

How about a nice game of Global Thermonuclear War?

[–] [email protected] 3 points 3 days ago

For that matter, even the Nagasaki bomb ("Fat Man") didn't use Uranium at all - its fuel was Plutonium.

[–] [email protected] 2 points 4 days ago

Oh, they do, but not as the primary or secondary. You can wrap depleated uranium around the core to capture fast neutrons that are leftover from the rest of the process. Changing the number of layers is how you can dial in a desired yield.

[–] [email protected] 1 points 4 days ago

Damnit, you're right and I'm wrong!

[–] [email protected] 3 points 4 days ago (1 children)

That's fissed, not fused.

[–] [email protected] 5 points 4 days ago

I stand corrected, because I done forgetted.