Download Terms to Know

Terms to Know
Alpha particles : The alpha particle (symbolized by the Greek letter α) is a positively
charged particle that makes up the nucleus of the helium atom (two protons and
two neutrons).
Artificial transmutation : An artificially induced nuclear reaction caused by the bombardment
of a nucleus with subatomic particles or small nuclei. There are two reactants.
Beta particles : A beta particle is an electron emitted by the nucleus of a radioactive atom.
Decomposition : A chemical reaction in which a compound is broken down into simpler
compounds or elements.
Fission : When a neutron strikes the nucleus of certain isotopes, the nucleus breaks or splits
apart into two roughly equal and smaller parts (lighter nuclei) in a process known as
nuclear fission.
Gamma radiation : Gamma radiation is one of the three forms of radiation emitted by
radioactive materials, the others being alpha and beta radiation. Gamma radiation consists
of gamma rays, high energy forms of electromagnetic radiation are somewhat similar to x
rays.
Natural decay : When a radioactive species ejects alpha, beta, gamma, and positron.
Natural transmutation : A nuclear reaction occurring naturally with one reactant.
Nuclear reaction : A nuclear reaction is a change that occurs in the nucleus of an
atom. Nuclear reactions are different from chemical reactions in that the latter involve the
gain and loss of electrons that orbit an atomic nucleus, but do not involve any change in the
nucleus itself
Positrons : The positron is the antiparticle of the electron. It has the same mass and the
same quantity of electric charge as does the electron, but its electric charge is positive
rather than negative.
Radioactivity : Radioactivity is the emission of radiation by unstable nuclei. That radiation
may exist in the form of subatomic particles (primarily alpha and beta particles) or in the
form of energy (primarily gamma rays).
Radioactive isotopes : The term radioisotope is shorthand for radioactive
isotope. Isotopes are forms of an element whose atoms differ from each other in the
number of neutrons contained in their nuclei and, hence, in their atomic
masses. Hydrogen(H), for instance has three naturally occurring isotopes. Hydrogen-1,
hydrogen-2, and hydrogen-3 are all isotopes of each other.