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Homework Help: Nuclear reaction?

  1. Jan 4, 2007 #1
    1. The problem statement, all variables and given/known data
    When (6 3)Li (i.e. 3 neurtrons and 3 protons) is bomarded with protons a nuclear reaction may occur in which an alpha particle is produced. What is the other product of this reaction? Write an equation for this reaction.

    2. Relevant equations
    conservation laws

    3. The attempt at a solution
    I got

    (6 3)Li + (1 1)H -> (4 2)He +(3 2)He

    but the back of the book doesn't agree.
  2. jcsd
  3. Jan 4, 2007 #2


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    Have you considered any isotopes of Hydrogen?
  4. Jan 4, 2007 #3
    The problem is the atomic and mass numbers must balance due to convervation. The question said only one other product is formed so it must be another Helium with two protons. Do you have other suggestions?
  5. Jan 4, 2007 #4


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    Ahh sorry, my mistake I misread the numbers :frown:. From what I can see, your reaction obeys all the relevant conservation laws (although I've only studied elementary Nuclear Physics) and your helium isotope is stable. What does the book suggest as the answer?
  6. Jan 4, 2007 #5
    Usually after a nuclear reaction the product is an isotope with more neutrons than the most common isotope? (3 2)He actually has less neutrons.

    But anyway, the answer suggeted (2 1)H
    How can this be?
  7. Jan 4, 2007 #6
    What book are you using? It seems if you use that answer and add in an alpha particle, you just get Li-6 back again. I would have added in the proton as well, but maybe the reaction is

    (6 3)Li + (1 1)p -> (4 2)He + (2 1)H + (1 1)p
  8. Jan 4, 2007 #7
    So you are suggesting the bombardment proton will not stick and you end up splitting (6 3)Li into an alpha particle plus a deutrium. And the original proton leaves unscathed. Conservation is certainl obeyed. That seems to make sense as the probabilty that proton sticks to the nucleus is low? Does the bombarding particle usually stick with the product of the reaction? I guess it depends on the product. (3 2)He is less stable than (2 1)H so that could be why the proton is left out on its own.
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