Search results for “pH”

Racemic Mixture Organic Chemistry degrees An equimolar mixture of two enantiomers, which shows no net optical rotation. 50:50 (+) and (−)

Radioactive Decay Series Nuclear & Radiochemistry Dimensionless A sequence of successive radioactive decays leading from a long-lived parent to a stable end product.

Radiocarbon Dating Nuclear & Radiochemistry years A dating technique that determines the age of organic material from its residual carbon-14 content. t = (t½ / 0.693) ln(N₀/N)

Reactant Stoichiometry & Chemical Reactions mol A starting substance that is consumed during a chemical reaction.

Redox Titration Analytical Chemistry & Spectroscopy mol/L A titration in which the reaction between titrant and analyte involves electron transfer.

Relative Lowering of Vapour Pressure Solutions & Colligative Properties Dimensionless The fractional reduction in a solvent's vapour pressure caused by dissolving a non-volatile solute. (p° − p) / p° = x_solute

Rutherford Model Atomic Structure & Periodicity Dimensionless The nuclear model of the atom, in which a tiny dense positive nucleus is surrounded by orbiting electrons in mostly empty space.

Salt Acids, Bases & Salts Dimensionless An ionic compound formed when the hydrogen of an acid is replaced by a metal or other cation. acid + base → salt + water

Salt Hydrolysis Acids, Bases & Salts mol/L The reaction of a salt's ions with water to produce an acidic or alkaline solution. A⁻ + H₂O ⇌ HA + OH⁻

Scintillation Counter Nuclear & Radiochemistry counts/s A detector in which radiation causes a material to emit flashes of light that are counted and measured.

Second Law of Thermodynamics Thermochemistry & Thermodynamics J/K The total entropy of the universe increases in every spontaneous process. ΔS_universe > 0

Secondary Cell Electrochemistry & Redox V A cell whose reaction can be reversed by an applied current, allowing it to be recharged and reused.

Secondary Structure Biochemistry & Polymer Chemistry Dimensionless Local regular folding patterns of a polypeptide backbone stabilised by hydrogen bonds.

Secondary Valence Inorganic & Coordination Chemistry Dimensionless In Werner's theory, the non-ionisable valence corresponding to the coordination number, satisfied by ligands in fixed spatial positions.

Selective Precipitation Chemical Equilibrium mol/L The separation of ions from a mixture by adding a reagent that precipitates them one at a time.

Self-Ionisation of Water Acids, Bases & Salts mol/L The reaction in which two water molecules transfer a proton to give a hydronium and a hydroxide ion. 2H₂O ⇌ H₃O⁺ + OH⁻

SI Base Units Foundations of Chemistry Various The seven defined units of the International System from which every other measurement unit is derived.

Sievert Nuclear & Radiochemistry Sv The SI unit of equivalent dose, weighting absorbed dose by the biological damage the radiation type causes. H = D × w_R

Slag Inorganic & Coordination Chemistry Dimensionless The molten by-product formed when a flux combines with the gangue during smelting.

Solid State States of Matter & Gas Laws Dimensionless The state of matter in which particles are held in fixed positions, giving a definite shape and volume.

Solubility Rules Stoichiometry & Chemical Reactions Dimensionless A set of empirical guidelines predicting whether an ionic compound will dissolve appreciably in water.

Solution Solutions & Colligative Properties Dimensionless A homogeneous mixture in which one or more substances are dispersed uniformly at the molecular or ionic level in another.

Solvent Solutions & Colligative Properties L The component of a solution present in the greater amount, which dissolves and disperses the solute.

Standard Molar Entropy Thermochemistry & Thermodynamics J/(mol·K) The absolute entropy of one mole of a substance in its standard state at 298 K. ΔS° = ΣS°(products) − ΣS°(reactants)

Results for “pH”