Question

If the total mass of the products of a reaction is less than the mass of the reactants, what must be true?
A nuclear reaction has taken place.
A chemical reaction has taken place.
Nuclear fusion has occurred.
Nuclear fission has occurred.

Answer 1

A nuclear fission must have occurred.

What is nuclear fission?

Nuclear fissions occur when heavy nuclei break down into 2 or light nuclei.

It is opposed to nuclear fusion in which 2 or more nuclei fuse together to form one heavy nucleus.

During nuclear fission, energy is released.  

Thus, the mass of the products in nuclear fission reactions is always less than the mass of the reactants.

More on nuclear fissions can be found here: https://brainly.com/question/913303

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