radioactivity: Radioactive Decay

The nuclei of elements exhibiting radioactivity are unstable and are found to be undergoing continuous disintegration (i.e., gradual breakdown). The disintegration proceeds at a definite rate characteristic of the particular nucleus; that is, each radioactive isotope has a definite lifetime. However, the time of decay of an individual nucleus is unpredictable. The lifetime of a radioactive substance is not affected in any way by any physical or chemical conditions to which the substance may be subjected.

Sections in this article:

• Introduction
• Discovery of Radioactivity
• Radioactive Disintegration Series
• Half-Life of an Element
• Radioactive Decay
• Gamma Radiation
• Beta Radiation
• Alpha Radiation
• Radioactive Emissions
• Bibliography

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