Chapter 43 - Energy from the Nucleus - Problems - Page 1330: 6d

$3$

The given fission reaction is ${}^{233}U+n→X+Y+bn$ It is given that $X={}^{141}Cs$ and $Y={}^{92}Rb$ Total mass number in left hand side of the above Eq. Is $(235+1)=236$ and total mass number of $X$ and $Y$ in left hand side of the above Eq. Is $(141+92+)=233$ According to conservation of mass number, the mass of $bn$ should be $(236-233)\;u=3\;u$ As, the mass number of $n$ is $1$, the value of $b$ should be $3$ So the complete Eq. becomes ${}^{233}U+n→{}^{141}Cs+{}^{92}Rb+3n$ Therefore the value of $b$ is $3$