Chapter 25 - Nuclear Chemistry

Radiation

Particles and rays emitted by radioactive matter.

Isotope

A form of an element where the number of protons does not equal the number of neutrons.

Radioisotope

Unstable isotopes that emit radiation to gain stability.

Nuclear reactions

Reactions that are not affected by temperature, pressure, or catalysts and cannot be slowed down, sped up, or stopped.

Becquerel

A French chemist who accidentally discovered radiation while studying uranium salts.

Marie and Pierre Curie

Associates of Becquerel who helped discover radiation.

Stability of a nucleus

The stability of a nucleus depends on the ratio of protons to neutrons and the overall size of the nucleus.

Radioactive decay

The process in which an unstable nucleus releases energy by emitting radiation spontaneously.

Alpha particle

A particle consisting of 2 protons, 2 neutrons, and a double positive charge, blocked by a sheet of paper.

Beta particle

An electron resulting from the breaking apart of a neutron, stopped by wood.

Gamma ray

A high-energy photon emitted by a radioisotope, often emitted along with alpha and beta particles, stopped by lead or concrete.

Band of stability

A region on a graph representing the number of neutrons vs the number of protons for stable nuclei.

Nuclear force

An attractive force that acts between all nuclear particles that are extremely close together.

Positron

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

Half-life

The time required for one half of a sample of a radioisotope to decay.

Transuranium elements

Elements with atomic numbers greater than 92 that do not occur naturally and are synthesized in nuclear reactors and accelerators.

Transmutation

The conversion of an atom of one element to another through radioactive decay or particle bombardment.

Fission

The splitting of atomic nuclei into smaller fragments, producing tremendous amounts of energy.

Fusion

The combining of atomic nuclei to produce a nucleus of greater mass, releasing more energy than fission.

Neutron activation analysis

A procedure used to detect trace amounts of elements in samples.

Ionizing radiation

Radiation emitted by radioisotopes with enough energy to knock electrons off atoms and produce ions.

Geiger counter

A device used to detect radiation.

Scintillation counter

A device used to detect radiation.

Film badge

A device used to detect radiation.

Neutron moderation

The process of slowing down neutrons in a nuclear reactor to continue the chain reaction.

Neutron absorption

The reduction of slow-moving neutrons before they hit fissionable matter in a nuclear reactor.

Nuclear waste

The spent rods in a nuclear reactor that are cooled by water and act as a radiation shield.