I

Isotope

ᴬ_Z X; e.g., ¹²C, ¹³C, ¹⁴C
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Quick Reference
Formula / Notationᴬ_Z X; e.g., ¹²C, ¹³C, ¹⁴C
Also Known AsIsotopes, nuclides (specific nuclear composition), radioisotopes, stable isotopes

What is Isotope?

Atoms of the same element (same atomic number) that have different numbers of neutrons and thus different mass numbers. Isotopes of an element have nearly identical chemical properties but different physical properties. Some isotopes are radioactive (radioisotopes).

Formula & Notation

ᴬ_Z X; e.g., ¹²C, ¹³C, ¹⁴C

Other Names / Synonyms: Isotopes, nuclides (specific nuclear composition), radioisotopes, stable isotopes

Properties & Characteristics

Isotopes are atoms of the same element (same atomic number Z, same number of protons) that have different numbers of neutrons, giving different mass numbers (A = Z + N). They have nearly identical chemical properties (slight kinetic isotope effect differences) but different nuclear properties (stability, radioactivity, mass). Natural isotope abundances are characteristic of each element. Stable isotopes are non-radioactive; radioisotopes decay with characteristic half-lives.

Uses & Applications

Isotopes are used in: isotopic labelling (tracing reaction mechanisms, metabolic pathways), radiometric dating (¹⁴C for archaeology, ²³⁸U for geology), nuclear medicine (¹⁸F-PET, ⁹⁹ᵐTc scintigraphy), nuclear power (²³⁵U, ²³⁹Pu as fissile fuels), industrial gauging (β-emitting thickness gauges), and stable isotope NMR spectroscopy (¹³C, ²H NMR).

Safety Information

Radioactive isotopes require radiation safety protocols (shielding, dosimetry, contamination control). Half-life determines the decay hazard duration. Long-lived radioisotopes (²³⁸U: 4.5 billion years; ¹³⁷Cs: 30 years) present long-term environmental and waste management challenges.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Isotope
Formula ᴬ_Z X; e.g., ¹²C, ¹³C, ¹⁴C
Synonyms Isotopes, nuclides (specific nuclear composition), radioisotopes, stable isotopes

Frequently Asked Questions

Atoms of the same element (same atomic number) that have different numbers of neutrons and thus different mass numbers. Isotopes of an element have nearly identical chemical properties but different physical properties. Some isotopes are radioactive (radioisotopes).

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Editorial standards: Chemical data is sourced from peer-reviewed literature, CAS Registry, NIST WebBook, and PubChem. Safety information reflects guidance from OSHA, ECHA, and IAEA. For educational purposes only — always consult official SDS documentation and qualified professionals before handling chemicals.