Concept Map

Key Terms

activity

the rate of decay for radioactive nuclides

alpha decay

type of radioactive decay in which an atomic nucleus emits an alpha particle

alpha rays

one of the types of rays emitted from the nucleus of an atom

antielectron

another term for positron

antimatter

composed of antiparticles

atomic mass

the total mass of the protons, neutrons, and electrons in a single atom

atomic number

number of protons in a nucleus

beta decay

type of radioactive decay in which an atomic nucleus emits a beta particle

beta rays

one of the types of rays emitted from the nucleus of an atom

binding energy

the energy needed to separate nucleus into individual protons and neutrons

daughter

the nucleus obtained when parent nucleus decays and produces another nucleus following the rules and the conservation laws

decay

the process by which an atomic nucleus of an unstable atom loses mass and energy by emitting ionizing particles

decay constant

quantity that is inversely proportional to the half-life and that is used in equation for number of nuclei as a function of time

decay equation

the equation to find out how much of a radioactive material is left after a given period of time

decay series

process whereby subsequent nuclides decay until a stable nuclide is produced

gamma decay

type of radioactive decay in which an atomic nucleus emits a gamma particle

gamma rays

one of the types of rays emitted from the nucleus of an atom

mass number

number of nucleons in a nucleus

neutrino

an electrically neutral, weakly interacting elementary subatomic particle

neutron

a neutral particle that is found in a nucleus

nuclear radiation

rays that originate in the nuclei of atoms, the first examples of which were discovered by Becquerel

nuclear reaction energy

the energy created in a nuclear reaction

nucleons

the particles found inside nuclei

nucleus

a region consisting of protons and neutrons at the center of an atom

parent

the original state of nucleus before decay

photomultiplier

a device that converts light into electrical signals

positron

the particle that results from positive beta decay; also known as an antielectron

positron decay

type of beta decay in which a proton is converted to a neutron, releasing a positron and a neutrino

protons

the positively charged nucleons found in a nucleus

radioactive

a substance or object that emits nuclear radiation

radioactive dating

an application of radioactive decay in which the age of a material is determined by the amount of radioactivity of a particular type that occurs

radioactivity

the emission of rays from the nuclei of atoms

More terms can be found in the chapter 31 in the textbook.