Suppose, we think of fission of a 5626Fe nucleus into two equal fragments, 2813Al. Is the fission energetically possible? Argue by working out Q of the process. Given m (5626Fe) = 55.93494 u and m (2813Al) = 27.98191 u.


The fission reaction can be given as :

The Q value for this reaction will be given as = [m()-2 × m()] × c2


= (55.93494-2 × 27.98191)u × c2 MeV


= -0.02888u × c2 MeV


= -0.02888 × 931.5


= -26.902MeV


The Q value is negative which suggests this reaction is endothermic, but we know fission reactions are exothermic. Hence, this fission reaction is not energetically possible.


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