- High energy particles or rays emitted during the nuclear decay processes.
- An atom or group of atoms that contains one or more unpaired electrons
(usually very reactive species)
- Radioactive Dating
- Method of dating ancient objects by determining the ratio of amounts of
mother and daughter nuclides present in an object and relating the ratio to the
object?s age via half-life calculations.
- Radioactive Tracer
- A small amount of radioisotope replacing a nonradioactive isotope of the
element in a compound whose path (for example, in the body) or whose
decomposition products are to be monitored by detection of radioctivity; also
called a radioactive label.
- The spontaneous disintegration of atomic nuclei.
- Raoult's Law
- The vapor pressure of a solvent in an ideal solution decreases as its mole
- Rate-determining Step
- The slowest step in a mechanism; the step that determines the overall rate
- Rate-law Expression
- Equation relating the rate of a reaction to the concentrations of the
reactants and the specific rate of the constant.
- Rate of Reaction
- Change in the concentration of a reactant or product per unit time.
- Substances consumed in a chemical reaction.
- Reaction Quotient
- The mass action expression under any set of conditions (not necessarily
equlibrium); its magnitude relative to K determines the direction in which the
reaction must occur to establish equilibrium.
- Reaction Ratio
- The relative amounts of reactants and products involved in a reaction;
maybe the ratio of moles. millimoles, or masses.
- Reaction Stoichiometry
- Description of the quantitative relationships among substances as they
participate in chemical reactions.
- Reducing Agent
- The substance that reduces another substance and is oxidized.
- The concept in which two or more equivalent dot formulas for the same
arrangement of atoms (resonance structures) are necessary to describe the
bonding in a molecule or ion.
- Reverse Osmosis
- Forcing solvent molecules to flow through a semipermable membrane from a
concentated solution into a dilute solution by the application of greater
hydrostatic pressure on concentrated side than the osmotic pressure opposing it.
- Reversible Reaction
- Reactions that do not go to completion and occur in both the forward and