| ρ-value (rho-value) |
| ρσ-equation (rho-sigma equation) |
value
in chromatography |
value in planar chromatographyquantity |
| rabbit |
| rac |
| racemate |
| racemic |
| racemic compound |
| racemic conglomerate |
| racemic mixture |
| racemization |
| racemo structures in polymers |
|
rad
unit |
| radial development |
| radial electrostatic field analyser
in mass spectrometry |
| radial elution (radial development) or circular elution
(circular development)
in planar chromatography |
|
radian
unit |
radiance,
quantity |
| radiant emittance |
radiant energy,
quantity |
radiant energy density,
 ,
quantity |
radiant exitance,
quantity |
radiant exposure,
quantity |
| radiant flux |
radiant (energy) flux,
 ,
quantity |
| radiant intensity |
radiant power,
 ,
quantity |
| radiant quantities |
| radiation |
| radiation chemistry |
| radiation constants |
| radiation continuum in spectrochemistry |
| radiation counter |
| radiation detector |
| radiation hazard |
| radiationless deactivation (decay) |
| radiationless transition |
| radiation spectrum |
| radiative absorption in spectrochemistry |
| radiative capture |
| radiative de-excitation in spectrochemistry |
| radiative energy transfer |
radiative lifetime,
quantity |
| radiative transition |
| radical (free radical) |
| radical anion |
| radical cation |
| radical centre(s) |
| radical combination |
| radical copolymerization |
| radical disproportionation |
| radical ion |
| radical pair (geminate pair) |
| radical polymerization |
| radicofunctional name |
| radioactive |
| radioactive age |
| radioactive chain |
| radioactive contamination |
| radioactive cooling |
| radioactive dating |
| radioactive decay |
| radioactive equilibrium |
| radioactive fallout |
| radioactive half life |
| radioactive series |
| radioactive source |
| radioactive tracer |
| radioactive tracer technique in analysis |
| radioactive waste |
| radioactivity |
| radioanalytical chemistry |
| radiochemical activation analysis |
| radiochemical purification |
| radiochemical purity |
| radiochemical separation |
| radiochemical yield |
| radiochemistry |
| radiochromatograph |
| radiocolloid |
| radioenzymatic assay |
| radiograph |
| radiogravimetric analysis |
| radioimmunoassay |
| radioiodination |
| radioisotope |
| radioisotope dilution analysis |
| radioisotope induced X-ray emission analysis |
| radioluminescence |
| radiolysis |
| radiometric analysis |
| radiometric titration |
| radiometry |
| radionuclide |
| radionuclidic purity |
| radioreceptor assay |
| radiorelease analysis |
| radiosonde |
radius of gyration,
|
| raffinate |
| rain out in atmospheric chemistry |
| random coil in polymers |
| random coincidence in nuclear chemistry |
| random copolymer |
| random copolymerization |
| random error |
| random sample |
| range in analysis |
| range of measurement of an analyser |
| Raoult's law |
| rate |
| rate coefficient |
rate constant,
|
| rate-controlling step |
| rate-determining step (rate-limiting step) |
| rate law (empirical differential rate equation) |
| ratemeter in radiochemistry |
| rate of appearance |
| rate of change of a quantity |
| rate of change ratio |
rate of consumption,
or
|
rate of conversion,
quantity |
| rate of disappearance |
rate of fluid consumption,
in flame emission and absorption spectrometryquantity |
rate of formation,
or
|
| rate of liquid consumption in flame spectroscopy |
rate of migration,
in electrophoresis |
| rate of nucleation |
rate of reaction,  quantity |
| ratio |
| raw coke |
| Rayleigh ratio |
| Rayleigh scattering |
| rayon-based carbon fibres |
reactance,
quantity |
| reactant |
| reacting bond rules |
| reaction |
| reaction barrier |
| reaction chromatography |
| reaction coordinate |
reaction cross-section,
quantity |
| reaction dynamics |
| reaction intermediate |
| reaction mechanism |
| reaction path |
| reaction path degeneracy |
reaction probability,
|
| reaction stage |
| reaction step |
| reaction time |
| reactive (reactivity) |
| reactive adsorption |
| reactive complex |
| reactive desorption |
| reactive scattering |
| reactivity index |
| reactivity–selectivity principle (RSP) |
| readability of a balance |
| reading |
| reagent |
| real (electrified) interphase |
| real potential of a species in a phase |
| real surface (interface) area |
| rearrangement |
| rearrangement ion in mass spectrometry |
| rearrangement stage |
| rebound reaction |
| receptor (1992, 64, 164)replaced |
| receptor (2004, 76, 1067) |
| receptor in drug design |
| recognition site |
| recoil in radioanalytical chemistry |
| recoil-free fraction in Mössbauer spectrometry |
| recoil labelling |
| recombinant DNA technology |
| recombination fluorescence |
| reconstructive transition |
| recovery |
| recovery factor in an extraction process |
| recrystallization |
| redox ion exchangers |
| redox polymers |
| red shift |
| redox potential |
| reduced adsorption |
| reduced limiting sedimentation coefficient |
reduced mass,
quantity |
reduced mobile phase velocity,
 in chromatography |
| reduced osmotic pressure |
| reduced sample |
| reduced sedimentation coefficient |
| reduced species |
| reduced viscosity of a polymer |
| reducing in analytical chemistry |
| reduction |
| reductive elimination |
| reductones |
| re-extraction |
| referee sample |
| reference atom
in organic reaction mechanisms |
| reference cell (or blank cell)
in spectrochemical analysis |
| reference dose (RfD) |
| reference electrode |
| reference material |
| reference method |
| reference procedure
in analysis of trace air constituents |
| reference state of an element |
| reference value pH standard |
reflectance,
quantity |
| reflection electron energy loss spectroscopy (REELS) |
| reflection factor |
| reflection high energy electron diffraction (RHEED) |
| refraction effects |
refractive index,  quantity |
| refractive index increment in polymer chemistry |
| regeneration of a catalyst |
| regioselectivity (regioselective) |
| regresssion analysis |
| regular block in a polymer |
| regular coke |
| regular comb macromolecule |
| regular macromolecule |
| regular oligomer molecule |
| regular polymer |
| regular single-strand polymer |
| regular star macromolecule |
| regulator gene |
| Reissert compounds |
| rel |
| relative |
| relative activity |
| relative adsorption |
relative atomic mass (atomic weight),
quantity |
| relative biological effectiveness of radiation |
| relative configuration |
| relative counting in nuclear chemistry |
relative density,
quantity |
| relative detection limit |
| relative electrode potential |
| relative elongation |
| relative error |
| relative humidity |
| relative local current density |
| relative micellar mass |
| relative molar mass |
relative molecular mass,
quantity |
relative permeability,
quantity |
relative permittivity,
quantity |
| relative preconcentration in trace analysis |
| relative responsivity |
relative retardation,
in planar chromatographyquantity |
relative retention,
in column chromatographyquantity |
| relative selectivity in catalysis |
| relative spectral responsivity |
relative standard deviation,
 ,
|
| relative uncertainty |
| relative viscosity |
| relative viscosity increment |
| relative volumic mass |
| relaxation |
| relaxation kinetics |
| relaxation time |
| releaser in analytical flame spectroscopy |
|
rem
unit |
| Renner–Teller effect |
| reorganization in polymers |
reorganization energy,
quantity |
| repeatability |
| (chain) repeating distance |
| repeating distance |
| repetency |
| replacement name |
| replacement operation in organic nomenclature |
| replicate (duplicate) sample |
| replication |
| report in analysis |
| reprecipitation |
| representative sample |
| repression |
| reproducibility |
| repulsive potential-energy surface |
| reserve sample |
| Re, Si |
| residence time |
residence time (hydraulic retention time),
in biotechnologyquantity |
| residual current |
| residual fuel/oil |
| residual liquid junction (potential) error
in pH measurement |
| residual spectrum/background spectrum
in mass spectrometry |
resistance,
quantity |
resistivity,
quantity |
| resolution in gas chromatography |
| resolution in mass spectroscopy |
| resolution in optical spectroscopy |
| resolution in stereochemistry |
| resolving power in mass spectrometry |
resolving power,
in optical spectroscopyquantity |
| resolving time
in nuclear analytical chemistry |
| resolving time correction
in nuclear analytical chemistry |
| resonance |
| resonance absorption technique |
| resonance broadening of a spectral line |
| resonance cross-section
in Mössbauer spectrometry |
| resonance effect |
| resonance effect magnitude
in Mössbauer spectrometry |
| resonance emission |
| resonance energy |
| resonance energy in radiochemistry |
| resonance fluorescence |
| resonance fluorescence technique |
resonance integral,
|
| resonance integral in radiochemistry |
| resonance lamp |
| resonance line in photochemistry |
| resonance line in X-ray spectroscopy |
| resonance neutrons |
| resonance radiation |
| response constant in electroanalytical chemistry |
response time,
of a detectorquantity |
| response time of an analyser |
responsivity,
in detection of radiationquantity |
| rest point of a balance |
| restricted rotation |
| restriction enzymes |
| result in analysis |
retardation factor,
in column chromatographyquantity |
retardation factor,
in planar chromatographyquantity |
| retarder |
| retentate |
| retention in nuclear chemistry |
| retention efficiency in particle separation |
retention factor,
in column chromatographyquantity |
retention index,
in column chromatographyquantity |
| retention of configuration |
| retention temperature in chromatography |
| retention time in chromatography |
| retention volumes in chromatography |
| reticulation in catalysis |
| retinoids |
| retro |
| retroaddition |
| retrocycloaddition |
| retro-ene reaction |
| reverse osmosis |
| reversed direct-injection burner
in analytical flame spectroscopy |
| reversed (radiochemical) isotope dilution analysis |
| reversed-phase chromatography |
| reverse micelle (or reversed micelle) |
| reverse transcriptases |
| reversible transition |
| revolutions per minute
(rpm)
|
| rheology |
| rheopexy |
| rhodamine dyes |
| rhombohedral graphite |
| ribonucleic acids (RNA) |
| ribonucleotides |
| ribosomal RNA (rRNA) |
| ribosomes |
| Rice–Ramsperger–Kassel (RRK) theory |
| Rice–Ramsperger–Kassel–Marcus (RRKM) theory |
| riffling in analytical chemistry |
| rigid chain |
| ring assembly |
| Ringelmann chart in atmospheric chemistry |
| ring-opening copolymerization |
| ring-opening polymerization |
| ring reversal (ring inversion) |
| ring-sector |
| rise time of a radiation detector |
| rise time of an analyser |
(vertical) rise velocity,
in flame emission and absorption spectrometry |
| risk |
| risk assessment |
| risk estimation |
| Ritchie equation |
| RNA |
|
röntgen
unit |
root-mean-square end-to-end distance,
in polymers |
| Rosanoff convention |
| rotamer |
| rotational barrier |
| rotational constants |
| rotational diffusion |
| rotational diffusion coefficient |
rotational frequency,
in centrifugationquantity |
rotational term,
quantity |
| rotator phase transition |
| rotatory power |
| rotaxanes |
| rotenoids |
| rotometer in atmospheric chemistry |
| roughness factor (rugosity) of a surface |
| rovibronic state |
| rRNA |
| RS |
| R, S |
| r, s |
| R*, S* |
| Rp, Sp |
| rubredoxin |
| ruby laser |
| rupture of a thin film |
| Rutherford backscattering (RBS) |
| Rydberg constantconstant |
| Rydberg orbital |
| Rydberg transition |
| RYDMR |
