🔬 Analytical, Lab & Spectroscopy
99 chemistry topics in Analytical, Lab & Spectroscopy, from beginner to intermediate to advanced level. Each topic has a clear explanation, a worked example, frequently asked questions and an interactive lesson.
Beginner topics in Analytical, Lab & Spectroscopy (25)
- Scientific MethodA systematic approach to inquiry using observation, hypothesis, experiment and conclusion.
- Laboratory SafetyWearing goggles, knowing hazards and handling chemicals correctly prevent accidents.
- Chemical Hazard SymbolsPictograms warn of flammable, corrosive, toxic and oxidizing substances.
- Measurement and UnitsThe SI system uses meters, kilograms, seconds, kelvin and moles as base units.
- Significant FiguresDigits in a measurement that carry meaning about precision.
- Accuracy and PrecisionAccuracy is closeness to the true value; precision is reproducibility of results.
- Scientific NotationExpressing numbers as a coefficient between 1 and 10 times a power of ten.
- Dimensional AnalysisConverting units using conversion factors that cancel unwanted units.
- DensityMass per unit volume, an intensive property that identifies substances.
- Percent CompositionThe mass percentage of each element in a compound.
- Empirical FormulaThe simplest whole-number ratio of atoms in a compound.
- Molecular FormulaThe actual number of each atom in a molecule, a multiple of the empirical formula.
- Balancing EquationsAdjusting coefficients so atoms of each element are equal on both sides.
- StoichiometryQuantitative calculation of reactants and products using mole ratios from balanced…
- Limiting ReagentThe reactant that is completely consumed first, limiting product formation.
- Theoretical and Percent YieldPercent yield is actual yield divided by theoretical yield times 100.
- Concentration CalculationsRelating moles, volume and molarity for solution preparation.
- Volumetric GlasswareBurettes, pipettes and volumetric flasks deliver or contain precise volumes.
- FiltrationSeparating insoluble solids from liquids using filter paper.
- DistillationSeparating liquids by differences in boiling points.
- CrystallizationPurifying a solid by dissolving in hot solvent and cooling to form crystals.
- Paper ChromatographySeparating pigments by how far they travel on paper, expressed as Rf values.
- Lab Notebook PracticeRecording observations, data and procedures clearly allows reproducibility.
- Graphing DataPlotting data reveals trends, and the slope or intercept can give physical constants.
- Laboratory Waste DisposalChemicals must be segregated and discarded by proper procedures.
Intermediate topics in Analytical, Lab & Spectroscopy (24)
- Standard SolutionsSolutions of accurately known concentration used in titration.
- Primary StandardsHigh-purity stable compounds, such as potassium hydrogen phthalate, used to prepare…
- Fractional DistillationRepeated vaporization-condensation using a column to separate close-boiling liquids.
- Steam DistillationSeparating temperature-sensitive compounds by distilling with steam.
- RecrystallizationRepeated crystallization to remove impurities from a solid.
- Solvent ExtractionSeparating compounds based on different solubility in immiscible solvents.
- Thin Layer ChromatographyRapid separation on a coated plate to check purity and monitor reactions.
- Column ChromatographyMixtures separated as they pass through a packed stationary phase.
- UV-Visible SpectroscopyMeasures absorbance of ultraviolet and visible light by electronic transitions.
- Beer-Lambert LawAbsorbance equals molar absorptivity times path length times concentration.
- ColorimetryMeasuring concentration of colored solutions by absorbance of light.
- Calibration CurveA graph of signal versus known concentration to determine unknowns.
- Infrared SpectroscopyIdentifies functional groups by absorption of IR radiation causing molecular vibrations.
- Gravimetric AnalysisDetermining amount of analyte by weighing a precipitate.
- Titrimetric AnalysisQuantitative analysis by measuring volume of reagent reacting with analyte.
- Redox TitrationsTitrations using oxidizing or reducing agents such as permanganate.
- Error AnalysisEvaluating random and systematic errors in measurement.
- Standard DeviationA measure of spread in repeated measurements.
- SamplingCollecting representative portions of material for analysis.
- CentrifugationSeparating components by density using rotational force.
- Refractive IndexA measure of how much light bends passing through a substance, used to identify liquids.
- Melting Point DeterminationA sharp melting range indicates a pure compound.
- Boiling Point DeterminationThe temperature at which vapor pressure equals ambient pressure.
- Flash PointThe lowest temperature at which vapors of a liquid can ignite.
Advanced topics in Analytical, Lab & Spectroscopy (50)
- Gas ChromatographyVolatile compounds separated by passage through a heated column with gas carrier.
- HPLCHigh-performance liquid chromatography separates compounds under high pressure.
- Retention TimeThe time a compound takes to elute from a chromatography column.
- Mass Spectrometry BasicsIons are separated by mass-to-charge ratio, giving molecular mass and fragmentation…
- Molecular Ion PeakThe peak in a mass spectrum corresponding to the intact ionized molecule.
- Fragmentation PatternsCharacteristic ion fragments help deduce molecular structure.
- Characteristic IR AbsorptionsC=O stretches near 1700 cm-1 and O-H stretches near 3300 cm-1 identify groups.
- Fingerprint RegionComplex IR region below 1500 cm-1 unique to each compound.
- Raman SpectroscopyUses inelastic scattering of light to probe vibrational modes.
- NMR SpectroscopyNuclei in magnetic fields absorb radio waves, revealing the structure of molecules.
- Chemical ShiftPosition of an NMR signal reflecting the electronic environment of a nucleus.
- Spin-Spin SplittingNeighboring hydrogens split NMR signals following the n+1 rule.
- Integration in NMRPeak area is proportional to the number of equivalent hydrogens.
- 13C NMRShows distinct carbon environments in a molecule.
- MRIMedical imaging based on proton NMR of water in tissues.
- Atomic Absorption SpectroscopyMeasures metal concentrations by absorption of light by free atoms.
- Flame PhotometryMeasures emission intensity of alkali metals in flames.
- ICP-MSInductively coupled plasma mass spectrometry detects trace elements at very low levels.
- X-ray CrystallographyDiffraction patterns of crystals reveal three-dimensional atomic positions.
- Electron MicroscopyUses electron beams to image structure at nanometre scale.
- Scanning Tunneling MicroscopyImages surfaces atom by atom using quantum tunneling current.
- Back TitrationAdding excess reagent then titrating the remainder to find analyte.
- Complexometric TitrationUses EDTA to determine metal ions such as calcium and magnesium.
- Potentiometric TitrationEquivalence point detected by following electrode potential.
- Conductometric TitrationEquivalence point located from changes in conductivity.
- Detection LimitThe lowest concentration reliably distinguished from background.
- Quality ControlProcedures such as blanks and standards ensure analytical reliability.
- ElectrophoresisCharged molecules separate in an electric field according to size and charge.
- Spectrophotometer DesignA light source, monochromator, sample cell and detector measure absorbance.
- FluorescenceEmission of light after absorption of higher-energy photons.
- PhosphorescenceDelayed emission from triplet states, causing glow-in-the-dark effects.
- ChemiluminescenceLight emission from a chemical reaction, as in glow sticks and luminol.
- Atomic Emission SpectroscopyExcited atoms emit characteristic wavelengths used for elemental analysis.
- PolarimetryMeasures rotation of polarized light by chiral substances.
- Thermogravimetric AnalysisMeasures mass change of a sample as temperature changes.
- Differential Scanning CalorimetryMeasures heat flow to detect melting, glass transitions and reactions.
- Computational ChemistryUses computers to model molecular structures and reactions.
- Density Functional TheoryA computational method that calculates electronic structure from electron density.
- Molecular DynamicsSimulation of atomic motion using classical equations.
- Hartree-Fock MethodAn approximate method for solving the many-electron Schrodinger equation.
- Born-Oppenheimer ApproximationNuclear and electronic motion can be separated because nuclei are much heavier.
- Particle in a BoxA quantum model with quantized energy levels used to illustrate confinement.
- Harmonic Oscillator ModelA quantum model of molecular vibration with equally spaced levels.
- Rigid Rotor ModelA quantum model for molecular rotation giving microwave spectra.
- Molecular SymmetrySymmetry operations classify molecules into point groups.
- Group Theory in ChemistryUses symmetry to predict spectra and orbital combinations.
- Selection RulesRules determining which spectroscopic transitions are allowed.
- Franck-Condon PrincipleElectronic transitions occur much faster than nuclear motion.
- Beer-Lambert LimitationsDeviations occur at high concentration due to molecular interactions and instrument…
- Green Analytical ChemistryMinimizing hazardous reagents and waste in analytical methods.
Frequently asked questions about Analytical, Lab & Spectroscopy
How many topics are in Analytical, Lab & Spectroscopy?
Analytical, Lab & Spectroscopy has 99 topics, from beginner to intermediate to advanced level.
Where should I start in Analytical, Lab & Spectroscopy?
Start with Scientific Method at the beginner level, then work through the topics in order.
Does every topic have an explanation and an example?
Yes. Each topic page has an in-depth explanation, a worked example, FAQs and links to related topics.