Ascientist is trying to determine whether a certain substance is radioactive. which question would be most to ask?

a. does the substance have a positive electric charge or a negative electric charge?

b. can the substance be used to generate electricity in a power plant?

c. do the atoms that make up the substance have nuclei that split apart over time?

d. do the nuclei of the substance’s atoms contain more neutrons than protons?

Answer is: C. Do the atoms that make up the substance have nuclei that split apart over time?

For example, nuclear fission is radioactive decay process in which the nucleus of an atom splits into smaller parts and huge amount of energy is released.

Radioactive atom spontaneously emits energetic particles or waves, while decays on lighter nuclei (atoms with smaller atomic mass).

Nuclear energy is the energy found in the nucleus of an atom.

"the periodic table is arranged in order of atomic number."