Isotopi

Isotopes are forms of an element where the number of neutrons in the nucleus varies, but the number of protons — the atomic number — is the same. This results in different atomic masses but does not affect the atom's charge.

Most elements have more than one isotope.

For example, elemental carbon has three naturally existing isotopes. Carbon-12, the most common of them, has six neutrons and six protons. The other two, carbon-13 and carbon-14, have seven and eight neutrons, respectively.

Carbon-12 and 13 are stable under natural conditions and do not decay into other elements over time.

On the other hand, carbon-14 has an unstable nucleus and decays into stable products over time by releasing energy. These are known as radioactive isotopes.

The decay of radioactive isotopes happens at a constant rate and forms the basis for radiometric dating, a technique used to estimate geological age.