How do isotopes of an element vary in nature?

Isotopes of an element vary in nature based on the number of neutrons in their atomic nucleus.

Isotopes are different forms of the same element that have the same number of protons but different numbers of neutrons in their atomic nucleus. This means that while they share the same atomic number (which defines the element), they have different mass numbers. The atomic number is the number of protons in an atom, and the mass number is the sum of protons and neutrons.

For example, carbon has three naturally occurring isotopes: carbon-12, carbon-13, and carbon-14. All carbon atoms have six protons, but carbon-12 has six neutrons, carbon-13 has seven, and carbon-14 has eight. Despite these differences, all three isotopes behave the same chemically because they have the same number of protons and electrons.

The variation in the number of neutrons among isotopes of the same element can affect the stability of the nucleus. Some isotopes are stable and do not change over time, while others are unstable or radioactive. These unstable isotopes, known as radioisotopes, can decay over time and emit radiation. For instance, carbon-14 is a radioactive isotope of carbon that decays over time, while carbon-12 and carbon-13 are stable.

The existence of isotopes is crucial in many scientific fields. In chemistry, isotopes help in understanding the structure and properties of atoms. In geology, isotopes are used for radiometric dating of rocks and fossils. In medicine, certain isotopes are used in diagnostic and therapeutic procedures. Therefore, understanding how isotopes of an element vary in nature is fundamental in science.