Question

Calculate the energy released by 1 g of natural uranium assuming 200 MeV is released in each fission event and that the fissionable isotope ${}^{235}U$ has an abundance of 0.7 % by weight in natural uranium.

Answer 1

235 gm uranium contains 6.02 $\times {10}^{23}$ nuclei

So, $\frac{6.02\times {10}^{23}}{235}=2.56\times {10}^{21}$ nuclei

So total energy released

= $5.12\times {10}^{23}\times 1.6\times {10}^{-19}\times {10}^6\times \frac{0.7}{100}$ Joule

= $5.7\times {10}^8$ J.