Consider the nuclear reaction ${ } _ { 1 } ^ { 3 } \mathrm { H } + { } _ { 1 } ^ { 3 } \mathrm { H } \rightarrow { } _ { 2 } ^ { 4 } \mathrm { He } + 2 { } _ { 0 } ^ { 1 } \mathrm { n }$. The known atomic masses are
${ } _ { 2 } ^ { 4 } \mathrm { He } : \quad 4.002603 \mathrm { u }$
${ } _ { 1 } ^ { 3 } \mathrm { H } : \quad 3.016049 \mathrm { u }$
${ } _ { 0 } ^ { 1 } \mathrm { n } : \quad 1.008665 \mathrm { u }$
What is the energy released (positive) or absorbed (negative) in this nuclear reaction? $( 1 \mathrm { u } = 931.5$ $\mathrm { MeV } / \mathrm { c } ^ { 2 }$ )

Question

Quizplus · Accepted Answer

The energy released in a nuclear reaction can be calculated using the mass defect, which is the difference between the mass of the reactants and the mass of the products, multiplied by $931.5 \, \text{MeV/c}^2$ (the conversion factor from atomic mass units to energy). For this reaction, the mass of the reactants is $2 \times 3.016049 \, \text{u} = 6.032098 \, \text{u}$, and the mass of the products is $4.002603 \, \text{u} + 2 \times 1.008665 \, \text{u} = 6.020033 \, \text{u}$. The mass defect is $6.032098 \, \text{u} - 6.020033 \, \text{u} = 0.012065 \, \text{u}$, which corresponds to an energy release of $0.012065 \, \text{u} \times 931.5 \, \text{MeV/u} = 11.3 \, \text{MeV}$.

Consider the Nuclear Reaction the Known Atomic Masses Are 24He:4.002603u{ } _ { 2 } ^ { 4 } \mathrm { He } : \quad 4.002603 \mathrm { u }24​He:4.002603u

Consider the Nuclear Reaction the Known Atomic Masses Are ${ } _ { 2 } ^ { 4 } \mathrm { He } : \quad 4.002603 \mathrm { u }$