isotopes
atoms of the same element that have different numbers of neutrons
radioactivity
the process by which an unstable nucleus gives off nuclear radiation
radioisotopes
an isotope that has an unstable nucleus and undergoes radioactive decay
radiation
energy that is radiated or transmitted in the form of rays or waves or particles
radioactive decay
the process in which a radioactive isotope tends to break down into a stable isotope of the same element or another element
alpha particle
a positively charged atom that is released in the disintegration of radioactive elements and that consists of two protons and two neutrons
beta particle
an electron emitted from the nucleus during some kinds of radioactive decay
gamma ray
electromagnetic radiation emitted during radioactive decay and having an extremely short wavelength, similar to an X-Ray but even more powerful
Atomic Number
the number of protons in the nucleus of an atom
mass number
the sum of the number of neutrons and protons in an atomic nucleus
nuclide
a specific atom with a designated number of protons and neutrons in its nucleus
alpha radiation
the radiation of alpha particles during radioactive decay, low penetrating power
beta radiation
radiation of beta particles during radioactive decay, medium penetrating power (1 cm of skin, several cm of wood, aluminum foil)
gamma radiation
electromagnetic radiation emitted during radioactive decay and having an extremely short wavelength, high penetrating power (can pass through body)
positron emission
a proton is converted into a neutron and a positron, atomic number decreases by one
positron
a positive electon
nuclear reaction
a high energy changeinvolving the atomic nucleus
nuclear equation
a shorthand representation using atomic notation to describe a nuclear reaction
electron capture
a nuclear decay reaction in which a heavy nuclide attracts one of its inner core electrons into the nucleus
parent-daughter nuclide
a term for the relationship between a decaying nuclide and the resulting nuclide that is produced
half life
the period of time in which half of a radioactive substance decays (t 1/2)
radionuclide
a nucleus of a pecific isotope of an element that is radioactive
transmutation
the conversion of an atom of one element to an atom of another element by a nuclear reaction
nuclear fission
a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
chain reaction
a series of fission reactions in which the product of one is a reactant in the next
deuterium
the nuclide of hydrogen with one neutron in the nucleus
binding energy
energy equivalent of the mass defect, hold atomic nucleus together
nuclear fussion
combination of the nuclei of small atoms to form to form a larger nucleus and releases energy
tritium
the nuclide of hydrogen with two neutrons in the nucleus
mass defect
the difference between the mass of a nuclide and the sum of the masses of the atom's protons, neutrons, and electrons
critical mass
the minimum mass of a fissionable nuclidethat is necessary to sustain a continuous chain reaction