Which one of the following is true?

(a) some spontaneous nuclear reactions are exothermic.
(b) some spontaneous nuclear reactions are endothermic.
(c) all spontaneous nuclear reactions are exothermic.
(d) there is no relationship between exothermicity and spontaneity in nuclear reactions.
(e) all spontaneous nuclear reactions are endothermic.

(C) All spontaneous nuclear reactions are exothermic.

Explanation:

the answer is option C

Here the Spontaneous nuclear reactions occur on its own. You don't have to have any outside force. Mass defects are converted into energy during the reaction.

Mass defects are the difference between the overall product mass and the overall reactant mass.

The expression ' ' shows both the mass defect and the energy emitted, where, C is the speed of light.

Because energy is always released in spontaneous nuclear reactions, all nuclear spontaneous reactions are always exothermic.

Hence the correct option is C

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