Search results for “pH”

Buffer Range Acids, Bases & Salts Dimensionless The span of pH values over which a buffer works effectively, conventionally one unit either side of its pKa. pH = pKa ± 1

Buffer Solution Acids, Bases & Salts Dimensionless A solution that resists changes in pH when small amounts of acid or base are added.

Calorimetry Thermochemistry & Thermodynamics J The experimental measurement of heat exchanged during a physical or chemical change. q = mcΔT

Cannizzaro Reaction Organic Chemistry Dimensionless The disproportionation of an aldehyde with no alpha hydrogen under concentrated alkali into an alcohol and a carboxylate. 2RCHO + OH⁻ → RCH₂OH + RCOO⁻

Cell Notation Electrochemistry & Redox Dimensionless A shorthand convention for representing an electrochemical cell using vertical lines for phase boundaries. Zn(s) | Zn²⁺(aq) ‖ Cu²⁺(aq) | Cu(s)

Counter Ion Inorganic & Coordination Chemistry Dimensionless An ion outside the coordination sphere that balances the charge of the complex ion.

Critical Point States of Matter & Gas Laws K, Pa The unique combination of temperature and pressure at which the liquid and gas phases of a substance become indistinguishable. (T_c, p_c)

Deposition States of Matter & Gas Laws kJ/mol The direct conversion of a vapour into a solid without an intermediate liquid phase.

Evaporation States of Matter & Gas Laws kJ/mol The escape of molecules from the surface of a liquid into the vapour phase below the boiling point.

Glass Electrode Electrochemistry & Redox V An ion-selective electrode whose thin glass membrane develops a potential proportional to the pH of the solution. E = constant − 0.0592 pH

Grignard Reagent Organic Chemistry Dimensionless An organomagnesium halide that acts as a source of a carbanion-like nucleophilic carbon. R–Mg–X

Henderson–Hasselbalch Equation Acids, Bases & Salts Dimensionless The equation giving the pH of a buffer from the pKa of its acid and the ratio of conjugate base to acid. pH = pKa + log([A⁻]/[HA])

Heterogeneous Catalysis Chemical Kinetics & Catalysis Dimensionless Catalysis in which the catalyst is in a different phase from the reactants, usually a solid with gaseous or liquid reagents.

Heterogeneous Equilibrium Chemical Equilibrium Dimensionless An equilibrium involving species present in more than one phase.

Heterogeneous Mixture Foundations of Chemistry Dimensionless A mixture in which the components remain physically distinct, so composition varies from one region of the sample to another.

Hexagonal Close Packing States of Matter & Gas Laws Dimensionless A close-packed arrangement in which layers of spheres repeat in an ABAB sequence. 6 atoms per cell, 74% packing

Homogeneous Catalysis Chemical Kinetics & Catalysis Dimensionless Catalysis in which the catalyst is in the same phase as the reactants.

Homogeneous Equilibrium Chemical Equilibrium Dimensionless An equilibrium in which all the reacting species are present in the same phase.

Hydrate Isomerism Inorganic & Coordination Chemistry Dimensionless Isomerism arising from water molecules occupying either the coordination sphere or lattice positions outside it.

Indicator Range Acids, Bases & Salts Dimensionless The span of pH over which an indicator's colour visibly changes, roughly one unit either side of its pKa. pH = pK_In ± 1

Interstitial Void States of Matter & Gas Laws Dimensionless An empty space between the packed spheres of a crystal lattice, capable of hosting a smaller ion or atom. r_void / r_sphere = 0.225 or 0.414

Ionisation Isomerism Inorganic & Coordination Chemistry Dimensionless Isomerism arising when an anion inside the coordination sphere exchanges places with the counter ion outside it.

Isoelectric Point Biochemistry & Polymer Chemistry Dimensionless The pH at which a molecule carries no net electrical charge. pI = (pKa₁ + pKa₂)/2

Lithium-Ion Battery Electrochemistry & Redox V A rechargeable cell in which lithium ions shuttle between a graphite anode and a metal oxide cathode. LiCoO₂ + C₆ ⇌ Li₁₋ₓCoO₂ + LiₓC₆

Results for “pH”