Answer:
B. the atomic weight of the element
Explanation:
since it talks about mass i think weight
Answer: Isotopes of an atom are different because they have different atomic masses and different number of neutrons within their nucleus. They are the same since they will always have the same atomic number/number of protons in their nucleus.
Explanation:
Answer:
Energy can neither be created nor destroyed, but it does change its form. And not all forms of energy are usable and it gets dissipated as heat energy and sound energy. The energy that is wasted cannot be recovered.
