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Physical Chemistry

Natural Radioactivity

Definition and meaning of Natural Radioactivity in chemistry.

Natural radioactivity is the spontaneous emission of radiation by unstable atomic nuclei that occur naturally in the environment. This process happens without any external influence or artificial stimulation.

In more detail

Elements with atomic numbers greater than 83 are typically naturally radioactive, meaning their isotopes spontaneously decay by emitting alpha particles, beta particles, or gamma rays. This decay releases energy and transforms the unstable element into a more stable atomic configuration over a specific time period. Background radiation on Earth largely comes from natural radioactivity found in rocks, soil, and high-energy cosmic rays entering the atmosphere.

Key facts

FieldPhysical Chemistry
DiscoveryHenri Becquerel in 1896
Common TypesAlpha, beta, and gamma radiation
Example

The continuous decay of carbon-14 found in organic materials is a form of natural radioactivity utilized in radiocarbon dating.

Frequently asked questions

Is natural radioactivity dangerous to humans?

While high doses are harmful, the low levels of background natural radioactivity we are exposed to daily are generally not considered dangerous.

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