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960 terms · page 22 of 40
Isotope Dilution Analysis
Nuclear & Radiochemistry
mol
A quantitative technique in which a known amount of labelled isotope is added and the resulting dilution measured.
n_unknown = n_spike(R_spike/R_mix − 1)
Isotopic Peak
Analytical Chemistry & Spectroscopy
Da
A peak appearing at a higher mass than the main ion because the molecule contains a heavier isotope.
M+1, M+2
IUPAC Nomenclature
Foundations of Chemistry
Dimensionless
The systematic naming rules issued by the International Union of Pure and Applied Chemistry that assign each substance one unambiguous name.
IUPAC Nomenclature of Complexes
Inorganic & Coordination Chemistry
Dimensionless
The systematic rules for naming coordination compounds unambiguously.
Jahn–Teller Distortion
Inorganic & Coordination Chemistry
pm
The geometric distortion of a complex that removes an electronic degeneracy and lowers its overall energy.
Joule–Thomson Effect
States of Matter & Gas Laws
K/Pa
The temperature change of a real gas when it expands through a throttle without exchanging heat or doing external work.
μ = (∂T/∂p)_H
Ketone
Organic Chemistry
Dimensionless
A compound containing a carbonyl group bonded to two carbon atoms.
R–CO–R′
Kinetic and Thermodynamic Control
Chemical Kinetics & Catalysis
Dimensionless
The distinction between a reaction giving the product that forms fastest and one giving the product that is most stable.
Kinetic Molecular Theory
States of Matter & Gas Laws
Dimensionless
The model that explains gas behaviour in terms of large numbers of tiny particles in constant random motion.
pV = ⅓ Nmc̄²
Kirchhoff's Law
Thermochemistry & Thermodynamics
kJ/mol
The relation describing how the enthalpy change of a reaction varies with temperature.
ΔH(T₂) = ΔH(T₁) + ΔC_p(T₂ − T₁)
Kohlrausch's Law
Electrochemistry & Redox
S·cm²/mol
At infinite dilution, the molar conductivity of an electrolyte is the sum of independent contributions from its cations and anions.
Λ°m = ν₊λ°₊ + ν₋λ°₋
Labile and Inert Complexes
Inorganic & Coordination Chemistry
s⁻¹
The kinetic classification of complexes according to how rapidly they exchange their ligands.
Langmuir Adsorption Isotherm
Chemical Kinetics & Catalysis
Dimensionless
A model describing monolayer adsorption on a surface with a fixed number of equivalent, independent sites.
θ = Kp / (1 + Kp)
Latent Heat
States of Matter & Gas Laws
kJ/kg
The energy absorbed or released when a substance changes state, with no accompanying change in temperature.
q = m × L
Lattice Energy
Chemical Bonding & Molecular Structure
kJ/mol
The energy released when one mole of an ionic solid is formed from its constituent gaseous ions.
U ∝ (z⁺z⁻) / (r⁺ + r⁻)
Law of Conservation of Mass
Foundations of Chemistry
kg
The principle that the total mass of the substances in a closed system is unchanged by any chemical reaction.
Σ m(reactants) = Σ m(products)
Law of Definite Proportions
Foundations of Chemistry
Dimensionless
The principle that a given chemical compound always contains its constituent elements in the same fixed mass ratio.
Law of Mass Action
Chemical Equilibrium
Various
The principle that the rate of a reaction is proportional to the product of the active masses of the reactants.
K = [C]^c[D]^d / [A]^a[B]^b
Law of Multiple Proportions
Foundations of Chemistry
Dimensionless
The principle that when two elements form more than one compound, the masses of one element combining with a fixed mass of the other are in small whole-number ratios.
Law of Radioactive Decay
Nuclear & Radiochemistry
Dimensionless
The principle that the rate of decay is proportional to the number of undecayed nuclei present.
N = N₀ e^(−λt)
Law of Reciprocal Proportions
Stoichiometry & Chemical Reactions
Dimensionless
The principle that the mass ratios in which two elements combine with a third are related by a simple ratio to the ratio in which they combine with each other.
Le Chatelier's Principle
Chemical Equilibrium
Dimensionless
When a system at equilibrium is disturbed, it responds in the direction that partially opposes the disturbance.
Leaching
Inorganic & Coordination Chemistry
Dimensionless
The selective dissolution of a metal or its compound from an ore using a suitable chemical reagent.
Lead–Acid Accumulator
Electrochemistry & Redox
V
A rechargeable cell using lead and lead dioxide electrodes in sulfuric acid.
Pb + PbO₂ + 2H₂SO₄ ⇌ 2PbSO₄ + 2H₂O