Why is nuclear fusion more powerful than nuclear fission?

Forgive me if this question is stupid.

From my limited knowledge, nuclear fusion means smashing atoms together to release energy, while nuclear fission means splitting apart atoms to release energy. If this is the case then shouldn’t fission be more powerful than fusion? From my knowledge of chemistry, atoms are held together by ionic and covalent bonds. These bonds are quite powerful. So, if we split atoms, we are overcoming these immensely powerful bonds. So shouldn’t this release a tremendous amount of energy?

I see one fault with my reasoning though. From my knowledge of how nuclear fusion works, atoms are accelerated to extremely high speeds and then smashed together. I am assuming that the energy released by forcing atoms to split apart releases more energy than smashing high-speed particles.

Is this the reason why fusion is more powerful than fission? Or is there another reason why?

Thank you for your time!

4 Answers

  • WOMBAT, Manliness Expert
    8 days ago

    This is a bit deceptive.

    In terms of MASS, Fusion does indeed produce more energy. If you fuse two grams of deuterium plus tritium (hydrogen isotopes) to produce two grams of helium you will produce more energy than if you fission two grams of uranium or plutonium.

    However, on an atom-by-atom basis, fission produces FAR more energy. Fissioning one atom of plutonium produces about 200 million electron volts (200 MeV) of energy. In contrast fusing one atom of deuterium and one atom of tritium to produce one atom of helium produces about 17 MeV. (BTW one MeV is not a lot of energy on human scale, but it’s massive on an atomic scale. If you fission millions of atoms every second, it adds up.)

    The difference lies in the fact that uranium or plutonium atoms are FAR HEAVIER than hydrogen atoms. One atom of uranium is 117.5 times more massive than an atom of deuterium (“aka heavy hydrogen”). Two grams of uranium is about the size of a grain of rice. two grams of deuterium will fill a beach ball.

    ~~~>Note that I’m not counting the energy required to “initiate” fusion, only the energy RELEASED by it.

    The practical way of creating fusion is to heat a mixture of hydrogen isotopes to unbelievably high temperatures. On the order of tens of millions of degrees. Such temperatures are normally only found at the cores of stars, or the barest moments after a nuclear bomb is triggered.

    At those temperatures the atoms are “banging around” at such high speeds that, very rarely, two atoms will collide at just the right angle and be able to overcome the mutual repulsion so the nuclei fuse together.

    In contrast fission can occur at room temperature or below. All you need to do is hit a uranium or plutonium atom with a neutron. Neutrons have no charge so they’re not repelled by the nucleus, so temperature isn’t a big factor. Free neutrons are themselves produced by fission events, so if you gather enough uranium or plutonium together in a confined area, you end up with a “chain reaction.” In principle it’s stupidly easy.

    Using a particle accelerator (“atom smasher”) isn’t practical because they’re ridiculously inefficient. very little of the electricity they use is actually converted into motion of the particles. Also, nearly all of the atoms accelerated thereby will simply zip by one another or be deflected like ricocheting bullets, without actually fusing together. Imagine trying to play a game of pool where all the balls are strongly repelled from one another. The minute the cue ball got anywhere close, the ball you were trying to hit would simply zip away like a fly escaping your hand. Oh yeah, and the nearest ball was thousands of miles away. You’d never hit anything.

    ~~~~> the reason why energy is produced by both fusion of light element and fission of very heavy, is difficult to explain. It has to do with the way the number of protons and neutrons affects the balance of forces in the nucleus. In contrast fission of light elements consumes energy and also fusion of heavy elements. A nucleus doesn’t “want” to have too few neutron or protons, but doesn’t want to have too many either. Like Goldilocks and the Three Bears.

  • ?
    4 days ago

    huge distinction. Nuclear explosions at the instant are not a hundred% useful in turning the fissile cloth into “Bang!”. Antimatter entering touch with count number is relatively distinctive proposition. it is going to bring about mutual annihilation. this is, total wipeout of the two gadgets without ashes or waste products. it incredibly is by using fact they might the two be at as quickly as became into potential – subsequently particularly warmth and lightweight. There may be a blast wave extending previous the annihilation website that would injury something cloth in variety and the radiated warmth might end off something ultimate. the quantity of potential released via an merchandise of roughly 1kg might in all possibility turn the planet Earth right into a cloud of airborne dirt and mud. i don’t think of that the international’s latest nuclear arsenal might do greater effective than wipe existence off of the outdoors of the planet whether they have been all detonated at as quickly as. the belief of a start up Trek style anti-count number engine is an relatively good distance into the destiny. initially – how do you exchange mutually annihilating cloth into something that can provide ‘thrust’, or electrical energy? it incredibly is not going that a nuclear potential station style of steam turbine might paintings.

  • Anonymous
    8 days ago

    Shattering a water soaked large spherical foam with bullets releases less water than the merging(squeezing) of two small spherical water soaked foams.

  • Prymer55
    6 days ago

    Because of magnets. How the f do they work???? Tides comes in, tide goes out. You can’t explain that. I before E except after C, and sometimes Y. Old McDonald had a farm and bingo was his name-o. You can’t explain that!

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