READ: Nuclear Chemistry Review
READ: Nuclear Chemistry Review
Radioactivity - the process in which an unstable nucleus changes by emitting particles or releasing energy.
Radiation - the particles or the energy that is released from the nucleus.
Nucleus – the central part of the atom housing the protons and neutrons.
Proton – a subatomic particle with a positive charge located in the nucleus of an atom and has a mass of 1 amu (atomic mass units).
Neutron – a subatomic particle with a neutral charge located in the nucleus of an atom and has a mass of 1 amu (atomic mass units).
Electron – a subatomic particle with a negative charge located orbiting around the nucleus within the electron cloud and has a mass of 1/1840 amu (atomic mass units).
Isotope - atoms that have the same number of protons but different numbers of neutrons.
Atomic number - the number of protons in an atomic nucleus.
Radioactive isotope – an isotope having an unstable nucleus that decomposes spontaneously by emission of nuclear radiation, thus achieving a stable nuclear composition.
Alpha particle - these particles consist of helium (He) nuclei, which are 2 protons and 2 neutrons, and are very large. Usually, a sheet of paper can stop them.
Beta particle - these particles consist of fast moving electrons (e-), which are much smaller and lighter than alpha particles. They have much more penetrating power, and a thick wooden board is required to stop them.
Gamma ray - this radiation is an extremely energetic form of light, which means it does not have a charge and is not made of matter. Usually several inches of lead or a few feet of concrete are required to shield people from the damaging effects of gamma radiation.
Isotopic notation - a method of specifying an isotope of an element by writing the symbol (A), mass number (x), and atomic number (y) as seen in the picture.
Alpha decay - a type of radioactive decay in which an atomic nucleus emits an alpha particle and thereby changes into an atom with a mass number 4 less and atomic number 2 less. Example:
Beta decay – a type of radioactive decay that is a result of a neutron splitting into a proton and an electron. The electron does not belong in the nucleus of the atom and is therefore shot out (beta particle). The resulting atom has the same mass and an atomic number increasing by one. Example:
Half-life - the time required for one-half of the atoms to undergo decay to isotopes of other atoms.
Decay curve - a graph line representing the decrease of radioactivity with the passage of time.
Fission - the process in which a nucleus splits into 2 or more smaller fragments releasing neutrons and a lot of energy.
Chain reaction - a series of fission processes in which the neutrons are emitted by a dividing nucleus and then cause the division of other nuclei.
Fusion - the process in which a light nucleus combines into heavier nucleus and releases energy.
Nuclear power plants - a thermal power station in which the heat source is a nuclear reactor that uses a series of fission chain reactions. The heat generated from these fission reactions is then used to generate steam which drives a steam turbine connected to a generator which produces electricity.
Georgia Virtual, Nuclear Chemistry, CC BY-NC-SA 3.0
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