13.15 The Q value of a nuclear reaction A + b $\to \mathit{}$ C + d is defined by

Q = [ ${\mathit{m}}_{\mathit{A}}+\mathit{}{\mathit{m}}_{\mathit{b}}$ – ${\mathit{m}}_{\mathit{C}}$ – ${\mathit{m}}_{\mathit{d}}$ ] ${\mathit{c}}^2$

where the masses refer to the respective nuclei. Determine from the given data the Q-value of the following reactions and state whether the reactions are exothermic or endothermic.

(i) ${}_1{}^1\mathit{H}$ + ${}_1{}^3\mathit{H}$ $\to$ ${}_1{}^2\mathit{H}$ + ${}_1{}^2\mathit{H}$

(ii) ${}_6{}^{12}\mathit{C}$ + ${}_6{}^{12}\mathit{C}$ $\to$ ${}_{10}{}^{20}\mathit{N}\mathit{e}$ + ${}_2{}^4\mathit{H}\mathit{e}$

Atomic masses are given to be

m ( ${}_1{}^2\mathit{H}$ ) = 2.014102 u

m ( ${}_1{}^3\mathit{H}$ ) = 3.016049 u

m ( ${}_6{}^{12}\mathit{C}$ ) = 12.000000 u

m ( ${}_{10}{}^{20}\mathit{N}\mathit{e}$ ) = 19.992439 u

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