Consider the nuclear reaction $\begin{array} { c } 14 \ 7 \end{array}$ N + $\begin{array} { l } 4 \ 2 \end{array}$ He ? $\begin{array} { l } 17 \ 8 \end{array}$ O + $\begin{array} { l } 1 \ 1 \end{array}$ H. The known atomic masses are $\begin{array} { c } 14 \ 7 \end{array}$ N: 14.003074 u $\begin{array} { l } 4 \ 2 \end{array}$ He: 4.002603 u $\begin{array} { l } 1 \ 1 \end{array}$ H: 1.007825 u $\begin{array} { l } 17 \ 8 \end{array}$ O: 16.999131 u What is the Q-value (or reaction energy)of this reaction? (1 u = 931.5 MeV/c²)

Question

Quizplus · Accepted Answer

The Q-value of the reaction is the difference in mass between the reactants and the products, multiplied by the speed of light squared. In this case, the reactants are $\begin{array} { c } 14 \7\end{array}$ N and $\begin{array} { l } 4 \2\end{array}$ He, and the products are $\begin{array} { l } 17 \8\end{array}$ O and $\begin{array} { l } 1 \1\end{array}$ H. The mass of the reactants is 14.003074 u + 4.002603 u = 18.005677 u, and the mass of the products is 16.999131 u + 1.007825 u = 18.006956 u. Therefore, the Q-value of the reaction is (18.005677 u - 18.006956 u) * 931.5 MeV/c² = -1.191 MeV.

Consider the Nuclear Reaction 147\begin{array} { c } 14 \\7\end{array}147​ N

Consider the Nuclear Reaction $\begin{array} { c } 14 \\7\end{array}$ N