Isotope dilution is a technique used to determine the concentration of a particular isotope of an element in a sample. This is done by adding a known amount of an isotope of the element to the sample and then measuring the change in the concentration of the isotope. The change in concentration is used to calculate the original concentration of the isotope in the sample.

Isotope notation is a way of representing the different isotopes of an element. The notation consists of the atomic number of the element, followed by a hyphen, followed by the mass number of the isotope. For example, carbon-12 is represented as 12C, while carbon-13 is represented as 13C.

Isotope dilution analysis is a powerful tool for measuring the concentration of isotopes in a sample. This technique has been used to determine the age of rocks, the origin of meteorites, and the sources of pollution.