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Atom Basic unit of chemical element
Electrons Subatomic particle with negative charges
Protons Subatomic particle with positive charges
Neutron Subatomic particle with neutral charges
Nucleus Central part of atom with protons and neutrons
Atomic number Number of protons in the nucleus of an atom
Atomic Mass Mass of an atom of chemical element
Mass number Total number of protons and neutrons in a nucleus
Isotope same form of an element with different number of neutrons
Average Atomic Mass Sum of masses of an element's isotopes multiplied by its natural abundance
Radioactivity Emission of Ionizing radiation or particles caused by disintegration of the nuclei
Alpha Particle A helium nucleus emitted by radioactive substances
Beta Particle Fast moving electron emitted by radioactive substances
Gamma ray Penetrating electromagnetic radiation
Half-Life Time taken for radioactivity of an isotope to fall to half its original value
Fission Diving or splitting something into two or more parts
Fusion Process or result of joining two or more things to form a single unity
Critical Mass Amount of starting material that makes each fission reaction produce at least on more fission reaction
Chain Reaction A series of fission reactions caused by neutrons released in each reaction
Tracer Radioactive isotope used to find or keep track of a molecule
Created by: Dante T.



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