Isotope

Isotope

An Isotope is a variant of a particular chemical element which differs in neutron number. All isotopes of a given element have the same number of protons but different numbers of neutrons in each atom.

Characteristics

Isotopes are distinguished by their mass number, which is the total number of protons and neutrons in the atomic nucleus. Isotopes are not separated in the periodic table; they are always grouped under a single element. Isotopes of the same element have almost identical chemical behavior, but they have different physical properties. Some isotopes are radioactive and are called radioisotopes, while others are stable.

Uses

Isotopes have many practical applications, including medicine, archaeology, and geology. In medicine, they are used in diagnostic imaging and in radiation therapy for cancer. In archaeology, isotopes are used in radiocarbon dating. In geology, isotopes are used to date rocks and to investigate the processes of earth and climate change.

Types of Isotopes

There are two types of isotopes: stable and radioactive. Stable isotopes do not decay into other elements. In contrast, radioactive isotopes decay over time. The rate of decay is specific to each isotope and is described by the half-life.

See also

• Radioactive decay
• Half-life
• Radiocarbon dating
• Radiation therapy

References

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  Hydrogen, Deuterium, and Tritium Nuclei Schematic
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  Discovery of Neon Isotopes
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  Isotopes and Half-life