Consider the nuclear reaction
\[
^{238}\mathrm{U}
\rightarrow
^{234}\mathrm{Th}
+
^{4}\mathrm{He}
\]
Take masses of
\(^{238}\mathrm{U}\),
\(^{234}\mathrm{Th}\),
and
\(^{4}\mathrm{He}\)
as
\[
238.050\,u,\qquad
234.043\,u,\qquad
4.003\,u
\]
respectively.
The \(Q\)-value for the reaction, in keV, is:
\[
1u = 931.5\ \mathrm{MeV}/c^2
\]