Module 11.1

nuclear energy

Energy stored in the nucleus of an atom

atoms

the simplest form of matter that cannot be broken down by chemical means

element

A substance composed of all the same type of atoms

isotopes

Atoms of the same element that have different numbers of neutrons

radioactive

A spontaneous process in which unstable nuclei lose energy by emitting radiation

fuel rods

A cylindrical tube that encloses nuclear fuel within a nuclear reactor

nuclear fission

a process that releases a tremendous amount of heat for the production of electricity

control rods

neutron-absorbing rods that help control the reaction by limiting the number of free neutrons

alpha radiation

Radiation that is made up of alpha particles; is deflected toward a negatively charged plate when radiation from a radioactive source is directed between two electrically charged plates

beta radiation

Radiation that is made up of beta particles; is deflected toward a positively charged plate when radiation from a radioactive source is directed between two electrically charged plates

gamma radiation

it is a high-energy photon (an electromagnetic wave) that can easily penetrate skin—it takes thick concrete or a dense material such as lead to stop gamma rays— giving it the greatest potential to cause serious health problems such as radiation sickness, cancer, and birth defects.

radioactive decay

A spontaneous process in which unstable nuclei lose energy by emitting radiation

radioactive half-life

the amount of time it takes for half of the radioactive material in question to decay to a new form. After one half-life, 50% of the material will decay; in the next half-life, 50% of what's left (or 25% of the original amount) will then decay, and so on. After 10 half-lives, just 0.1% of the original radioactive material is left.

Low-level radioactive waste (LLRW)

material that has low amounts of radiation relative to its volume and can usually be safely buried

High-level radioactive waste (HLRW)

spent nuclear reactor fuel or waste from the production of nuclear weapons that is still highly radioactive

Nuclear Waste Policy Act

(1982) U.S. government must develop a high level nuclear waste site (Yucca Mtn)