Light nuclei can combine to release energy

PHYSICS · Multi-part · CBSE · Physics · Nuclei · Nuclei

Problem

Light nuclei can combine to release energy. Consider the fusion reaction:

^2_1\text{H} + ^3_1\text{H} \rightarrow ^4_2\text{He} + n

. The relevant atomic masses are

m(^2_1\text{H}) = 2.0141\,\text{u}

m(^3_1\text{H}) = 3.0160\,\text{u}

m(^4_2\text{He}) = 4.0026\,\text{u}

and

m(n)=1.0087\,\text{u}

. (i) Calculate the mass defect

\Delta m

for the reaction in atomic mass units. (ii) Find the energy released

Q

per fusion event in (a) MeV, and (b) joules, using

1\,\text{u}=931.5\,\text{MeV}

and

1\,\text{eV}=1.6\times10^{-19}\,\text{J}

. (iii) Compute the percentage of the initial mass that is converted into energy in this fusion reaction.