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960 terms · page 32 of 40
Radiometric Dating
The general technique of determining the age of a sample from the decay of a radioactive nuclide it contains.
Nuclear & RadiochemistryRadiopharmaceutical
A radioactive compound administered to a patient for diagnosis or treatment.
Nuclear & RadiochemistryRadiotherapy
The medical use of ionising radiation to destroy cancerous tissue.
Analytical Chemistry & SpectroscopyRaman Spectroscopy
A vibrational technique based on the small shift in frequency of light scattered inelastically by molecules.
Analytical Chemistry & SpectroscopyRandom Error
An error that varies unpredictably in size and direction between repeated measurements.
Solutions & Colligative PropertiesRaoult's Law
The partial vapour pressure of each component of an ideal solution equals its mole fraction times its pure vapour pressure.
Chemical Kinetics & CatalysisRate Constant
The proportionality constant in a rate law, characteristic of a given reaction at a given temperature.
Chemical Kinetics & CatalysisRate Law
An experimentally determined equation expressing reaction rate as a function of reactant concentrations.
Chemical Kinetics & CatalysisRate-Determining Step
The slowest step in a reaction mechanism, which limits the overall rate.
Stoichiometry & Chemical ReactionsReactant
A starting substance that is consumed during a chemical reaction.
Chemical Kinetics & CatalysisReaction Intermediate
A species produced in one step of a mechanism and consumed in a later one, so it does not appear in the overall equation.
Chemical Kinetics & CatalysisReaction Mechanism
The detailed sequence of elementary steps by which reactants are converted into products.
Chemical EquilibriumReaction Quotient
The same ratio as the equilibrium constant but evaluated with the concentrations actually present at any moment.
Chemical Kinetics & CatalysisReaction Rate
The change in concentration of a reactant or product per unit time.
Foundations of ChemistryReagent
A substance added to a system to bring about a chemical reaction or to test for the presence of another substance.
States of Matter & Gas LawsReal Gas
An actual gas whose behaviour deviates from the ideal gas law because its molecules occupy volume and attract one another.
Stoichiometry & Chemical ReactionsRearrangement Reaction
A reaction in which the atoms of a molecule are reorganised to give a structural isomer.
Electrochemistry & RedoxRedox Couple
The oxidised and reduced forms of the same species, considered together as a conjugate pair.
Stoichiometry & Chemical ReactionsRedox Reaction
A reaction in which electrons are transferred, so that one species is oxidised while another is reduced.
Analytical Chemistry & SpectroscopyRedox Titration
A titration in which the reaction between titrant and analyte involves electron transfer.
Electrochemistry & RedoxReducing Agent
A species that donates electrons to another substance and is itself oxidised in the process.
Biochemistry & Polymer ChemistryReducing Sugar
A sugar with a free aldehyde or ketone group that can reduce mild oxidising agents.
Electrochemistry & RedoxReduction
The gain of electrons by a species, accompanied by a decrease in its oxidation number.
Electrochemistry & RedoxReference Electrode
A half-cell with a stable, known and reproducible potential, used as a fixed point against which other potentials are measured.