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  1. Radioactivity | Definition, Types, Applications, & Facts ...

    Apr 7, 2026 · radioactivity, property exhibited by certain types of matter of emitting energy and subatomic particles spontaneously. It is, in essence, an attribute of individual atomic nuclei.

  2. Radioactive decay - Wikipedia

    Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation.

  3. Radioactivity and the Types of Radioactive Decay

    May 30, 2021 · Radioactivity is defined as the emission of particles and radiation from nuclear reactions. These nuclear reactions include radioactive decay by unstable atomic nuclei, fission, and fusion. It’s …

  4. Radiation Basics | Nuclear Regulatory Commission - NRC

    Despite their ability to penetrate other materials, in general, neither gamma rays nor x-rays have the ability to make anything radioactive. Several feet of concrete or a few inches of dense material (such …

  5. DOE Explains...Radioactivity | Department of Energy

    Radioactivity is the release of energy from the decay of the nuclei of certain kinds of atoms and isotopes. Atomic nuclei consist of protons and neutrons bound together in tiny bundles at the center of atoms.

  6. The Science Behind Radioactive Elements

    May 1, 2025 · These unstable atoms release excess energy in the form of radiation — a process called radioactive decay. As atoms decay, they turn into different elements or isotopes in their attempt to …

  7. The Radioactive Atom: An Overview | Radiation and Your Health ...

    Feb 22, 2024 · But some atoms have an unstable combination blend of protons and neutrons, and these are considered radioactive. To get to a more stable state, the atom expels energy from the nucleus in …