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Converting Helium back to Hydrogen?

  1. Aug 20, 2011 #1
    I am trying to find the reason why a helium atom cannot be turned back into a hydrogen atom.

    We know in a star that through nucleosynthesis helium is formed from hydrogen and the process continues to form heavier elements. Is there a similar, but in reverse process where lighter elements are formed from heavier elements?
     
  2. jcsd
  3. Aug 20, 2011 #2

    DaveC426913

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    Gold Member

    Yes. It's called fission. :smile:

    But it takes a lot of energy to separate helium into hydrogen.
     
  4. Aug 20, 2011 #3
    Thanks for the quick reply.
     
  5. Aug 21, 2011 #4
    You need to study the binding energy curve.

    Basically atoms lighter than iron release energy in fusion and take in energy for fission

    whilst

    Basically atoms heavier than iron release energy in fission and take in energy for fusion

    Here is a more complete answer

    http://csep10.phys.utk.edu/astr162/lect/energy/bindingE.html

    also look up the packing fraction curve.
     
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