What are isotopes? Select all that apply.

Isotopes are atoms of the same element that have the same number of protons but a different number of neutrons. This means that they have the same atomic number but different atomic mass numbers. For example, carbon-12, carbon-13, and carbon-14 are all isotopes of carbon. They all have 6 protons, but carbon-12 has 6 neutrons, carbon-13 has 7 neutrons, and carbon-14 has 8 neutrons.
Isotopes have the same chemical properties, but they can have different physical properties. For example, some isotopes are radioactive, while others are not.
Isotopes are used in a variety of applications, including medicine, industry, and research. For example, radioactive isotopes are used in medical imaging and cancer treatment. Isotopes are also used to date fossils and rocks.