The energy released in a nuclear reaction is due to:

The figure shows a plot of binding energy per nucleon $E_b$ against the nuclear mass number $A$. $A, B, C, D, E, F$ correspond to different nuclei. Consider four reactions:
$(i) A + B \to C + \varepsilon$
$(ii) C \to A + B + \varepsilon$
$(iii) D + E \to F + \varepsilon$
$(iv) F \to D + E + \varepsilon$
Here, $\varepsilon$ is the energy released. In which reactions is $\varepsilon$ > 0?

The binding energy per nucleon for a deuteron and an $\alpha$-particle are $x_1$ and $x_2$ respectively. The energy $Q$ released in the following reaction is:
$_1H^2 + _1H^2 \rightarrow {_2}{He}^4 + Q$

Draw conclusions from the two main features of the graph of binding energy per nucleon versus the atomic mass number $(A)$.

Calculate the energy equivalent of $1\; g$ of substance.

The energy equivalent of $1 \text{ kg}$ of matter is about