The particle that should complete the reaction is 2/1H.
What is a nuclear reaction?
The term nuclear reaction has to do with the process in which a change occurs in the nucleus of atoms.
We can see that the reaction shown is a nuclear fusion, from the products, we can be able to deduce that the particle that should complete the reaction is 2/1H. The complete reaction equation is therefore; [tex]\frac{3}{1} H + \frac{2}{1} H ---- > \frac{4}{2} He + \frac{1}{0} n + Energy[/tex]
Learn more about nuclear fusion:https://brainly.com/question/12701636
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