Question

For nuclei with mass number close to $119$ and $238$, the binding energies per nucleon are approximately $7.6MeV$ and $8.6MeV$ respectively. If a nucleus of mass number $238$ breaks into two nuclei of nearly equal masses, what will be the approximate amount of energy released in the process of fission?

• A. 214 MeV
• B. 119 MeV
• C. 2047 MeV
• D. 1142 MeV

Answer 1

Answer: (A)

$119\to 7.6MeV$
$238\to 8.6MeV$
$238\to 119+119$
$E_i=238\times 8.6,$
$E_f=238\times 7.6$
$\therefore E_f-E_i=-238MeV$
A negative value indicates the fission cannot take place.
The data given are incorrect.
The BE per nucleon values are swapped in question, it should have been $7.6MeV$ for $238$ and $8.6MeV$ for $119$.
Thus $\Delta E=+238MeV$.
Thus $214$ is closest and will be taken as right answer