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Nuclear chemistryUses of radioisotopes and carbon dating

Nuclear chemistry is the study of the breakup of unstable nuclei, which results in the emission of radiation and energy. There are three types of radiation; alpha (伪), beta (尾) and gamma (纬).

Part of ChemistryChemistry in society

Uses of radioisotopes and carbon dating

Uses of radioisotopes

Radioisotopes of elements have a wide variety of uses.

Cobalt-60Used in medicine to treat cancer. Gamma rays can be focused on tumors.
Iodine-131Used to treat thyroid gland (in the neck). If the gland is enlarged, iodine-131 can be absorbed and will partially destroy it.
Carbon-14Used to date once-living materials.
Cobalt-60
Used in medicine to treat cancer. Gamma rays can be focused on tumors.
Iodine-131
Used to treat thyroid gland (in the neck). If the gland is enlarged, iodine-131 can be absorbed and will partially destroy it.
Carbon-14
Used to date once-living materials.

Carbon dating

Every living organism contains the radioisotope carbon-14. Carbon-14 is formed when neutrons from cosmic radiation collide with nitrogen atoms in our atmosphere forming protons and carbon-14 atoms.

\(_0^1n + _{\,\,7}^{14}N \to _{\,\,6}^{14}C + _1^1H\)

Carbon dioxide is responsible for carbon-14 entering the food chain.

Carbon-14 decays by beta-emission and has a half-life of 5730 years. This means that the beta-decay emissions can be monitored and the data used to calculate how long it has been since the material was alive.

A log buried underground. At age 0 its beta decay activity is 100%. After 5,730 years this has dropped to 50%. After 11,460 years it has dropped to 25%. After 17,190 years beta decay activity is 12.5% of its original value.
Figure caption,
Carbon 14 decay of a buried log. Its activity has dropped to 12.5% after 17,190 years.

Radioisotopes are used to detect and treat cancer and have various uses in industry

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