2
$\begingroup$

I am given that the mass deficit of 114-Cd is -90.01 MeV, and asked to calculate the binding energy, which should simply be 90.01 MeV then, due to the use of natural units (i.e. where $c=1$). I'm then asked to calculate the binding energy per nucleon which should simply be $\frac{90.01}{114}$. However, according to the solutions manual, the binding energy per nucleon is 8.54 MeV instead. I'm not entirely sure where the discrepancy arises. Any help would be appreciated.

$\endgroup$
1
  • $\begingroup$ The mass deficit of cadmium appears to be about 1AMU or 931MeV. (1.0086654 neutron * 48 + 1.00727647 proton * 66 - 113.9033585(29) mass cadmium= delta m = 0.99282772 aprox 1) $\endgroup$
    – JMLCarter
    Jan 29, 2017 at 1:52

1 Answer 1

1
$\begingroup$

The mass deficit is related to, but different from, the binding energy. The bare neutron and bare proton have zero binding energy, while the canonical source for mass deficits defines $\Delta[{}^{12}\rm C] = 0$. Note also that the NNDC mass deficits are for neutral atoms, and therefore include electron masses.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.