You cannot create something from nothing and similarly you cannot create less from more, if you didn't balance an equation that needs to be balanced, your product might end up equalling more or less than the total mass of the two elements combined. Which is impossible
Answer: Radioisotopes are used by manufacturers as tracers to monitor fluid flow and filtration, detect leaks, and gauge engine wear and corrosion of process equipment. Small concentrations of short-lived isotopes can be detected whilst no residues remain in the environment.
Explanation: Uranium-235 is used for nuclear fission and as a fuel in nuclear reactors.
An isotope of cobalt is used in the treatment of cancer.
An isotope of iodine is used in the treatment of goiter.
I am not sure about my answer, but I think that it's density allows it to fall to the ground/floor.