Nuclear Radiation

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Nuclear Chemistry Noun

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[noo-klee-er kem-is-tree]

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Nuclear Chemistry

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The field of chemistry concerned with the structure of atomic nuclei and the changes they undergo during nuclear reactions.

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Example: This graph shows that for a radioactive substance, the amount decreases by half after each 'half-life' period, demonstrating the principle of radioactive decay.

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Nuclear Reaction Noun

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[noo-klee-er ree-ak-shun]

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Nuclear Reaction

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A reaction that occurs when nuclei combine, split, or emit radiation, often converting one element into another element.

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Example: A large, unstable parent nucleus (Uranium-238) undergoes a nuclear reaction, splitting into a smaller daughter nucleus (Thorium-234) and releasing an alpha particle.

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Valence Electrons Noun

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[vay-lense ih-lek-trons]

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Valence Electrons

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The electrons located in the outermost shell of an atom that are directly involved in forming chemical bonds with other atoms.

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Example: This atomic model of Boron shows electrons in different shells; the outermost electrons, called valence electrons, are distinguished from the inner core electrons.

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X-rays Noun

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[eks-rayz]

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X-rays

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A form of high-energy electromagnetic radiation emitted when electrons strike certain materials or when inner-shell electrons are displaced.

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Example: This diagram shows X-rays are a type of high-energy electromagnetic wave, positioned on the spectrum between ultraviolet light and highly radioactive gamma rays.

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Phosphorescence Noun

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[fos-fuh-res-uhns]

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Phosphorescence

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A phenomenon in which certain minerals emit light after being exposed to an energy source, such as sunlight.

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Example: This diagram shows an electron absorbing UV energy, jumping to a higher energy level, and immediately emitting a photon as it returns to its ground state, illustrating fluorescence.

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Radioactivity Noun

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[ray-dee-oh-ak-tiv-i-tee]

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Radioactivity

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The process by which unstable atomic nuclei spontaneously give off energetic rays and particles to become more stable.

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Example: A radioactive atom is unstable and releases energy and particles, a process called radioactive decay, to become more stable.

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Radiation Noun

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[ray-dee-ay-shun]

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Radiation

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The energetic rays and particles, such as alpha particles, beta particles, and gamma rays, emitted by a radioactive source.

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Example: A radioactive atom is unstable and releases energy and particles from its nucleus; this emission is called nuclear radiation.

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Isotopes Noun

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[ahy-suh-tohps]

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Isotopes

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Atoms of the same element that have the same number of protons but contain different numbers of neutrons.

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Example: Isotopes are atoms of the same element with the same number of protons but a different number of neutrons, like Hydrogen, Deuterium, and Tritium.

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Radioisotopes Noun

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[ray-dee-oh-ahy-suh-tohps]

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Radioisotopes

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Isotopes of atoms that possess unstable nuclei and spontaneously emit radiation to achieve a more stable configuration.

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Example: The unstable radioisotope Carbon-14 decays, transforming into stable Nitrogen-14 by releasing a beta particle, a form of nuclear radiation.

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Radioactive Decay Noun

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[ray-dee-oh-ak-tiv di-kay]

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Radioactive Decay

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The process in which an unstable nucleus releases energy by emitting radiation to attain a more stable atomic configuration.

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Example: An unstable parent nucleus (uranium-238) releases a small particle (an alpha particle), changing into a new, more stable daughter nucleus (thorium-234).