Q.

The disintegration energy Q for the nuclear fission of U235→C140e+Z94r+n is ___ MeV.

(Given atomic masses of U235:235.0439u; C140e:139.9054u; Z94r:93.9063u; n:1.0086u, and value of c2=931 MeV/u.)


Ans.

(208)

U235→C140e+Z94r+n

Disintegration energy

Q=(mR-mP)c2,  mR=235.0439 u

mP=139.9054 u+93.9063 u+1.0086 u=234.8203 u

Q=(235.0439 u-234.8203 u)c2

   =0.2236 c2

   =0.2236×931

Q=208.1716