The fallout from a nuclear explosion and the waste from a nuclear reactor contain radioactive isotopes..?

Question

he fallout from a nuclear explosion and the waste from a nuclear reactor contain radioactive isotopes. The atoms of these isotopes differ from stable atoms in that.....

Answer 1

They have different numbers of neutrons. Isotopes of a certain element all have the same number of protons but different numbers of neutrons. This changes their atomic mass and a number of other properties dealing with nuclear stability.