Unit 2 Vocab

Scintillation counter

________- uses a phosphor- coated surface to detect radiation, designed to detect all types of ionizing radiation.

Geiger counter

________- uses a gas- filled metal tube to detect radiation; can detect alpha, beta, and gamma radiation.

Radioactivity

________- the process by which materials give off rays.

Proton

________- positively subatomic particle with a mass of about 1840 times that of an electron.

smallest particle

Atom- ________ of an element that retains its identity in a chemical reaction.

Band of stability

________- a region where the stable nuclei are located.

Radioistopes

________- the nuclei of unstable isotopes.

Beta particle

________- an electron resulting from the breaking apart of a neutron in an atom.

tiny central core

Nucleus- the ________ of an atom and is composed of protons and neutrons.

Neutron

________- subatomic particle with no charge but with a mass nearly equal to that of a proton.

Radiation

________- the penetrating rays and particles emitted by a radioactive source.

Positron

________- a particle with the mass of an electron but a positive charge.

Transmutation

________- the conversion of an atom of one element to an atom of another element through either radioactive decay or the bombardment of the nucleus of an atom by particles.

Isotopes

________- atoms that have the same number of protons but different numbers of neutrons.

Electron

________- negatively charged subatomic particles.

Fission

________- when the nuclei of certain isotopes are bombarded with neutrons, splitting the nucleus into smaller fragments.

Gamma ray

________- a high- energy photon emitted by a radioisotope.

Cathode ray

________- glowing beam that travels within a(n) ________ tube from the cathode (negative electrode) to the anode (positive electrode)

Half life

________- the time required for one- half of the nuclei of a radioisotope sample to decay to products.

Periodic table

________- an arrangement of elements in which the elements are separated into groups based on a set of repeating properties, allowing you to easily compare the properties of one element (or a group of elements) to another element (or group of elements)

atom

smallest particle of an element that retains its identity in a chemical reaction

atomic mass

a weighted average mass of the atoms in a naturally occurring sample of the element, reflecting both the mass and the relative abundance of the isotopes as they occur in nature

atomic mass unit (amu)

one twelfth of the mass of a carbon-12 atom

atomic number

the number of protons in the nucleus of an atom of that element

cathode ray

glowing beam that travels within a cathode ray tube from the cathode (negative electrode) to the anode (positive electrode)

electron

negatively charged subatomic particles

group

aka family, each vertical column of the periodic table

isotopes

atoms that have the same number of protons but different numbers of neutrons

mass number

the total number of protons and neutrons in an atom

neutron

subatomic particle with no charge but with a mass nearly equal to that of a proton

nucleus

the tiny central core of an atom and is composed of protons and neutrons

period

each horizontal row of the periodic table

periodic table

an arrangement of elements in which the elements are separated into groups based on a set of repeating properties, allowing you to easily compare the properties of one element (or a group of elements) to another element (or group of elements)

proton

positively subatomic particle with a mass of about 1840 times that of an electron

alpha particle

a particle emitted by alpha radiation that contains two protons and two neutrons and and has a double positive charge

band of stability

a region where the stable nuclei are located

beta particle

an electron resulting from the breaking apart of a neutron in an atom

film badge

a badge consisting of several layers of photographic film covered with black light-proof paper, all encased in a plastic or metal holder that must be worn for the entire duration of work as an important radiation detector for people who work near any type of radiation source

fission

when the nuclei of certain isotopes are bombarded with neutrons, splitting the nucleus into smaller fragments

fusion

when nuclei combine to produce a nucleus of greater mass (more energy is released from the combination of small nuclei in fusion than the splitting of large nuclei in fission)

gamma ray

a high-energy photon emitted by a radioisotope

Geiger counter

uses a gas-filled metal tube to detect radiation; can detect alpha, beta, and gamma radiation

half-life

the time required for one-half of the nuclei of a radioisotope sample to decay to products

ionizing radiation

radiation with enough energy to knock electrons off some atoms of the bombarded substance to produce ions

neutron absorption

the process that decreases the number of slow-moving neutrons, uses control rods made of materials like cadmium

neutron activation analysis

a procedure used to detect trace amounts of elements in samples

neutron moderation

the process that slows down neutrons so the reactor fuel (uranium-235 or plutonium-239) captures them to continue the chain reaction, necessary as most neutrons produced move so fast they will pass right through a nucleus without being absorbed, works well with the moderators water and carbon as graphite

positron

a particle with the mass of an electron but a positive charge

radiation

the penetrating rays and particles emitted by a radioactive source

radioactivity

the process by which materials give off rays

radioistopes

the nuclei of unstable isotopes

scintillation counter

uses a phosphor-coated surface to detect radiation, designed to detect all types of ionizing radiation

transmutation

the conversion of an atom of one element to an atom of another element through either radioactive decay or the bombardment of the nucleus of an atom by particles

transuranium elements

the elements in the periodic table with atomic numbers above 92 (the atomic number of uranium) which all undergo transmutation