Question

Consider the fission `._(92)U^(238)` by fast neutrons. In one fission event, no neutrons are emitted and the final stable and products, after the beta decay of the primary fragments are `._(58)Ce^(140)` and `._(44)Ru^(99)`. Calculate Q for this fission process, The relevant atomic and particle masses are:
`m(._(92)U^(238))=238.05079u, m(._(58)Ce^(140))=139.90543 u, m(._(34)Ru^(99))=98.90594 u`

Answer 1

for the fission reaction, `._(92)U^(238)+._0n^1to._(58)Ce^(140)+._(34)Ru^(99)+Q`
mass defect, `Deltam= "mass of" U^(238)+"mass of n-(mass of" Ce^(140)+"mass" Ru^(99))`
`=238.05079+1.00867-(139.90543+98.90594)=0.24809u`
`Q=0.24809xx931MeV=230.97MeV`