How does carbon 14 differ from carbon 12 and 13?

There are multiple isotopes of carbon; the most prevalent ones are carbon-12, 13, and 14. All of these isotopes have the same mass number but distinct atomic numbers.

Since carbon has an atomic number of six, all of its isotopes share the same proton count.

But the amount of neutrons varies, resulting in varying mass numbers: there are six neutrons in carbon-12, seven in carbon-13, and eight in carbon-14.

Since carbon-12 and carbon-13 are stable isotopes, radioactive decay of the nucleus is not observed.

Beta decay is the process by which one of carbon-14's neutrons turns into a proton. Carbon-14 has an unstable nucleus that is subject to radioactive decay.

This is the process of transmutation, whereby the number of protons increases by one, resulting in an atomic number of seven instead of six. The new element is nitrogen.

In carbon dating, specific fossils are dated using carbon-14.

Carbon-14 has two more neutrons than carbon-12 and one more neutron than carbon-13.