nuclear binding energy
the energy released when a nucleus is formed from nucleons
band of stability
stable nuclei cluster over a range of neutron-proton ratios
nuclear reaction
reaction that affects the nucleus of an atom
transmutation
change in identity of a nucleus as a result of a change in the number of its protons
mass defect
difference between an atom's mass and the sum of the masses of its protons neutrons and electrons
binding energy per nucleon
binding energy of nucleus divided by the number of nucleons
nucleon
a proton or neutron
nuclide
An atom that is identified by the number of protons and neutrons in its nucleus
nuclear shell model
nucleons exist in different energy levels or shells in the nucleus
magic numbers
2,8,20,28, 50, 82,126
radioactive decay
spontaneous disintegration of a nucleus into a slightly lighter nucleus accompanied by an emission of particles, electromagnetic radiation or both
electromagnetic radiation
a form of energy that exhibits wavelike behavior as it travels through space
nuclear radiation
particles or electromagnetic radiation emitted from the nucleus during radioactive decay
radioactive nuclide
an unstable nucleus that undergoes radioactive decay
alpha particle
2 protons and 2 neutrons bound together and emitted from the nucleus during radioactive decay
beta particle
an electron emitted from the nucleus during radioactive decay
positron
particle with the same mass as an electron with a positive charge emitted from the nucleus during radioactive decay
electron capture
inner orbital electronis captured by the nucleus of its own atom
gamma rays
high energy electromagnetic waves emitted from a nucleus as it changes from an excited state to a ground energy state
half life
time required for half the atoms of a radioactive nuclide to decay
decay series
series of radioactive nuclides produced by successive radioactive decay until a stable nuclide is reached
parent nuclide
heaviest nuclide of each decay series
daughter nuclides
nuclides produced by the decay of parent nuclides
artificial transmutations
bombardment of stable nuclei with charged and uncharged particles
transuranium elements
elements with more than 92 protons
roentgen
unit used to measure nuclear radiation; equal to the amount of radiation that produces 2 x 10^9 ion pairs when it passes through 1 cm^3 of dry air
rem
quantity of ionizing radiation that does as much damge to human tissue as 1 roentgen of high voltage x rays
film badges
use exposure of film to measure approximate radiation exposure of those working with it
geiger muller counters
instruments that detect radiation by counting electric pulses carries by a gas ionized by radiation
scintillation counters
instruments that convert scintillating light to an electric signal for detecting radiation
radioactive dating
process by which the apporximate age of an object is determined based on the amount of certain radioactive nuclides
radioactive tracers
radioactive atoms incorporated into substances so that movement of the substances can be followed by radiation detectors
nuclear waste
radioactive waste material produced by nuclear power plants
nuclear fission
nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
nuclear fussion
light mass nuclei combine to form a heavier, more stable nucleus
chain reaction
reaction in which the material that starts the reaction is also one of the products and can start another reaction
critical mass
minimum mass of fissionable material that can sustain a chain reaction
nuclear reactors
use controlled-fission chain reactions to produce energy and radioactive nuclides
nuclear power plants
use energy as heat from nuclear reactors to produce electrical energy
shielding
radiation-absorbing material that is used to decrease radiation exposure from nuclear reactors, especially gamma rays
control rods
neutron-absorbing rods that help control the reaction by limiting the number of free neutrons
moderator
used to slow down fast neutrons produced by fission