Bombardment of Nitrogen-14 with an alpha particle

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SUMMARY

The discussion centers on the bombardment of nitrogen-14 with alpha particles, resulting in the formation of oxygen-17 and the release of a proton. The kinetic energy of the reaction products was calculated, with participants arriving at different values, including 1.65 MeV and 1.81 MeV. A critical point raised was the need for precise atomic mass values to accurately determine the q-value of the reaction, which was noted to be -1.192 MeV, indicating that the reaction is endothermic. A correction was also mentioned regarding the nitrogen mass used in calculations.

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agent5514
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Question:
When alpha particles, having kinetic energy 3.0000 MeV bombard nitrogen-14 nuclei, oxygen-17 forms and the reaction releases a proton. Calculate the kinetic energy shared by the reaction products.
Nitrogen-14 = 14.000307 amu
Helium-4 = 4.00260 amu
Oxygen-17 = 16.99913 amu
Proton = 1.00727 amu
1 amu = 931 MeV

Attempt at question:
I cannot derive the textbook answer (1.65 MeV). I found the increase in mass to be 0.00073 amu which equals 0.67963 MeV. I subtract this from 3.0000 MeV, but I got instead 2.32037 MeV. Does anyone know how to obtain the textbook solution? Thanks a lot.
 
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Hi,
If you want to calculate the q-value of the reaction you must have a better precision in your atomic mass (see https://www-nds.iaea.org/amdc/ame2016/mass16.txt)
If you take this mass number you will have Q=-1.192 MeV. Q <0 because the reaction is endothermic (threshold reaction)
PSR
 
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You should use the isotopic mass of 1H, otherwise you miss an electron (the other isotope masses are with electrons).

If I calculate it, the reaction is not even possible.

Edit: You have a typo in the nitrogen mass, there is one more zero than it should be.

I get 1.81 MeV.
 
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