With the half life of the radioactive metals used in the fuel rods being thousands of years, the fuel used in reacors, i would think, should last for similar amounts of time. How come nuclear plants go through large ammount of spent fuel that then has to be stored?
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Think of it like a bunch of dominoes standing on end – and “half-life” is how long it typically takes half of all independent dominos to tip over because of a tiny breeze, etc.
If these dominoes are set up very far apart, then one domino randomly tipping over only releases a tiny amount of kinetic energy and isn’t likely to knock any others over. This is where the natural independent “radioactive decay” idea comes into play, and is how “half-life” is defined.
On the other hand, if there are very many dominoes standing next to each other, then one domino tipping over might push two others, which might push into four others, with might push into eight others, etc. All of these dominoes (except the very first one) didn’t “decay” naturally, they were all pushed! So, the amount of fallen dominoes is more a question of “How closely packed are the dominoes?” and “How long on average does a chain-reaction of domino falls last?” rather than a question of isolated “half-life”.
Nuclear reactors burn through fuel quickly compared to the fuel half-life because they are designed to sustain those long chain-reactions that release more energy faster.
Think of it like a bunch of dominoes standing on end – and “half-life” is how long it typically takes half of all independent dominos to tip over because of a tiny breeze, etc.
If these dominoes are set up very far apart, then one domino randomly tipping over only releases a tiny amount of kinetic energy and isn’t likely to knock any others over. This is where the natural independent “radioactive decay” idea comes into play, and is how “half-life” is defined.
On the other hand, if there are very many dominoes standing next to each other, then one domino tipping over might push two others, which might push into four others, with might push into eight others, etc. All of these dominoes (except the very first one) didn’t “decay” naturally, they were all pushed! So, the amount of fallen dominoes is more a question of “How closely packed are the dominoes?” and “How long on average does a chain-reaction of domino falls last?” rather than a question of isolated “half-life”.
Nuclear reactors burn through fuel quickly compared to the fuel half-life because they are designed to sustain those long chain-reactions that release more energy faster.
Uranium-235’s half-life is 700 *million* years. It’s not even warm to the touch. Fissioning it releases much more energy than it would decaying to lead, and much, *much*, **much** faster. So that’s useful for human purposes.
I wouldn’t say it’s a large amount of spent fuel, considering the amount of energy released. Each fuel pellet — the size of a fingertip — releases about as much a ton of coal.
Uranium-235’s half-life is 700 *million* years. It’s not even warm to the touch. Fissioning it releases much more energy than it would decaying to lead, and much, *much*, **much** faster. So that’s useful for human purposes.
I wouldn’t say it’s a large amount of spent fuel, considering the amount of energy released. Each fuel pellet — the size of a fingertip — releases about as much a ton of coal.
Uranium-235’s half-life is 700 *million* years. It’s not even warm to the touch. Fissioning it releases much more energy than it would decaying to lead, and much, *much*, **much** faster. So that’s useful for human purposes.
I wouldn’t say it’s a large amount of spent fuel, considering the amount of energy released. Each fuel pellet — the size of a fingertip — releases about as much a ton of coal.
Nuclear fission works by a neutron (a tiny particle) hitting an atom of uranium-235, causing it to split into two new atoms, both of which are smaller.
These new atoms can’t be used in a nuclear reaction but still have a lot of mass (only a teeny amount is turned into energy) so the spent fuel rod still has a mass which is almost identical to the “new” rod, hence a lot of waste being produced after the reaction because these new atoms are quite unstable in their own right.
Nuclear fission works by a neutron (a tiny particle) hitting an atom of uranium-235, causing it to split into two new atoms, both of which are smaller.
These new atoms can’t be used in a nuclear reaction but still have a lot of mass (only a teeny amount is turned into energy) so the spent fuel rod still has a mass which is almost identical to the “new” rod, hence a lot of waste being produced after the reaction because these new atoms are quite unstable in their own right.
Nuclear fission works by a neutron (a tiny particle) hitting an atom of uranium-235, causing it to split into two new atoms, both of which are smaller.
These new atoms can’t be used in a nuclear reaction but still have a lot of mass (only a teeny amount is turned into energy) so the spent fuel rod still has a mass which is almost identical to the “new” rod, hence a lot of waste being produced after the reaction because these new atoms are quite unstable in their own right.
That’s like comparing the rate at which wood rots to the rate at which it *burns*. Radioactive decay is the spontaneous decomposition of unstable atoms. Nuclear fission inside a reactor is a chain-reaction which *causes* the atoms to split, harnessing the exothermic products of the reaction to heat water and drive aturbine.
The [U235 decay chain](https://www.chemistrylearner.com/uranium-235.html#:~:text=this%20radioactive%20metal.-,Uranium%2D235%20Radioactive%20Decay,decay%20energy%20of%204.679%20MeV.) goes like this:
>Uranium-235 →Thorium-231 → Protactinium-231 →Actinium-227 →Thorium-227 →Radium-223 →Radon-219 →Polonium-215 →Lead-211 →Bismuth-211 →Thallium-207→ Lead-207 (stable)
The fission products of a nuclear reactor are far less predictable, but include isotopes of Iodine, Caesium, Strontium, Xenon, and Barium. That’s because the neutrons which collide with the U235 nuclei crack them apart.
That’s like comparing the rate at which wood rots to the rate at which it *burns*. Radioactive decay is the spontaneous decomposition of unstable atoms. Nuclear fission inside a reactor is a chain-reaction which *causes* the atoms to split, harnessing the exothermic products of the reaction to heat water and drive aturbine.
The [U235 decay chain](https://www.chemistrylearner.com/uranium-235.html#:~:text=this%20radioactive%20metal.-,Uranium%2D235%20Radioactive%20Decay,decay%20energy%20of%204.679%20MeV.) goes like this:
>Uranium-235 →Thorium-231 → Protactinium-231 →Actinium-227 →Thorium-227 →Radium-223 →Radon-219 →Polonium-215 →Lead-211 →Bismuth-211 →Thallium-207→ Lead-207 (stable)
The fission products of a nuclear reactor are far less predictable, but include isotopes of Iodine, Caesium, Strontium, Xenon, and Barium. That’s because the neutrons which collide with the U235 nuclei crack them apart.
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