how the nucleus of an atom is actually split to create an atomic bomb?
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With scissors, it’s a very tedious process but when it comes time someone’s gotta do it. I assume it’s some sort of punishment in the military to be the guy that splits it. Probably a pretty severe one and that explains why only a couple have gone off.
Fission. The isotopes uranium-235 and plutonium-239 were selected by the atomic scientists because they readily undergo fission. Fission occurs when a neutron strikes the nucleus of either isotope, splitting the nucleus into fragments and releasing a tremendous amount of energy.
Imagine a marble. You shoot a glass fragment at it so hard that the marble shatters, mostly into 2 pieces. Some of the glass fragments from the marble shattering go on to split other marbles, and those split to send out more shards to split more marbles, and soon you have a growing cloud of speeding glass shards. Once everything’s done shattering, you have tiny glass particles floating in the air, and the marble halves are on the ground, making it hard to walk without cutting yourself
Only instead of marbles, you have an atomic nucleus made of protons and neutrons. The neutrons are the glass shards. They hit the nucleus and disrupt the balance, leaving radioactive isotopes (the marble halves) and speeding neutrons (glass shards) that go to hit other atoms in a chain reaction.
This is how a fission bomb works. Fusion bombs are kinda the opposite. The glass halves fuse together and create light and heat, which makes the right environment for more fusion
This whole thread gave me a flashback to my youth before I had even a middle school understanding of chemistry. My knowledge at that point was limited to “atoms are the smallest bits of matter”. So in my head an oxygen atom and a uranium atom were just two different balls. No concept of subatomic particles. So at that age, the very concept of splitting the atom was mind boggling to me. It definitely didn’t help that neither of my parents had taken chemistry in high school, so they couldn’t answer my burning questions either.
Jokes on them, I went on to study applied analytical chemistry as part of an environmental science program.
Ever played pool/snooker? When you break the initial bunch of balls?
Same idea: subatomic particles (protons and neutrons) get separated by an outside particle (the cue ball) and they scatter in every direction. In atoms, though, the group of balls is held together by a very strong attractive energy.
In an atomic explosion, the energy needed to fire the cue ball is much less than the energy released when the balls are separated.
I like [this](https://www.youtube.com/watch?v=vjqIJW_Qr3c) analogy. Imagine a floor covered by mousetraps. Each mousetrap is primed to go off, and a ping pong ball is placed on top of it. If the mousetrap goes of, it will fling the ping pong ball. Each mousetrap has a small probability of randomly going off. If hit by a ping pong ball, the mousetrap *will* go off.
Once one trap goes of, the flung ping pong ball might hit multiple other traps. Each of those will go off, setting off still more traps. This starts what is known as a chain reaction, with the number of traps going off increasing exponentially, because each trap that goes off is able to set off multiple other traps. The triggering of traps also releases energy (in this case, causing the ping pong balls and triggered traps to fly about).
In the analogy, the primed mousetrap is like a uranium nucleus, the ping pong ball is like a neutron within the uranium nucleus, and the triggered trap is like the byproduct of uranium fission.
Think of a radioactive atom like a tiny grenade that will sometimes shoot off a piece of shrapnel. If that shrapnel hits another grenade, it will knock off another piece of shrapnel, and now there are two pieces of shrapnel flying around, but most of the time it hits something that won’t break off another piece. This happens naturally underground in ore deposits, and emits a small amount of energy.
If you surround a chunk of radioactive material in something that will reflect that shrapnel, the chances of it hitting another grenade are increased. This will start a chain reaction that will gradually release more and more shrapnel flying around. This is what happened in the demon core.
If you surround the radioactive material in a normal explosive like C4 and detonate it simultaneously, it shoves all those grenades together into a super compressed ball where each shrapnel has a much higher chance of hitting another grenade. This produces an explosive release of energy seen in atomic bombs.
How is the nucleus split? Small atoms like hydrogen or helium are bound very tightly. A few protons, neutrons and the strong nuclear force holds them together. In the nucleus of each atom of uranium-235 (U-235) are 92 protons and 143 neutrons, for a total of 235. This is unstable, there’s too much stuff. They even break by themselves, we call that radioactivity. When you throw a free neutron in that big unstable nucleus, it shakes for a bit, then breaks apart and sends other free neutrons. That how the nucleus splits.
We don’t split atoms by sending neutrons at the nucleus like in pool. The neutron has to be going at a low speed in order to join the nucleus. The latter becomes unstable and breaks apart. If the neutron is going to fast, you cannot split other atoms with it because it won’t stick on the nucleus
The nucleus is like a ball of glue (neutrons) and magnets that are all repelling each other (protons). But the balance is delicate and just right to keep it together. And it was forced together with quite a bit of energy when it was made in a star.
When a stray bit of glue comes along and hits the ball, it is too much to handle and the ball falls apart. This splits into a few large pieces, some single bits of glue (neutrons) and the energy from when it was made. If your bomb is crafted properly, at least one of these neutrons will hit the neighbouring atoms and cause another fission. This chain reaction will affect the whole material and release a huge amount of energy.
You slam it with a particle like a rock to a bunch of sedimentary rocks. Pop goes the nucleus, sending out other particles to slam into other atoms.
(Ironically I actually have a degree in this. But this is the best ELI5 I could come up with. 😀 )
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