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Homework Help: Stellar structure - Helium burning

  1. Nov 11, 2012 #1
    1. The problem statement.
    Calculate the energy generated per unit mass, if helium burning produces equal amounts (mass fractions) of carbon and oxygen.
    mH = 1.672621581 x 10^-27 kg

    2. The attempt at a solution
    Helium burning produces carbon according to the following reaction:
    3He -> C [E(released) = 7.275 MeV]

    Helium burning produces oxygen according to the following reactions:
    3HE -> C [E(released) = 7.275 MeV]
    He + C -> O [E(released) = 7.162 MeV]
    ______________________________________________ overall reaction for He:
    4He -> O [E(released) = 14.437 MeV]

    equal mass fractions => X(C) = X(O)
    => m(C)/m(total) = m(O)/m(total)

    And then? I have no idea how to continue the exercise. Can anyone provide me with a hint?

    Last edited: Nov 11, 2012
  2. jcsd
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