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960 terms · page 10 of 40
Critical Temperature
States of Matter & Gas Laws
K
The temperature above which a gas cannot be liquefied by pressure alone, however great.
T_c = 8a / 27Rb
Cross-Linking
Biochemistry & Polymer Chemistry
Dimensionless
The formation of covalent bonds between separate polymer chains.
Cryoscopic Constant
Solutions & Colligative Properties
K·kg/mol
The freezing point depression produced by a one-molal solution of a non-electrolyte in a given solvent.
K_f = RT_f²M / ΔH_fus
Crystal Defect
States of Matter & Gas Laws
Dimensionless
Any irregularity that interrupts the perfectly ordered arrangement of particles in a crystal.
Crystal Field Splitting Energy
Inorganic & Coordination Chemistry
cm⁻¹
The energy difference between the sets of d orbitals produced when a ligand field lifts their degeneracy.
Δ₀ or Δ_t
Crystal Field Stabilisation Energy
Inorganic & Coordination Chemistry
kJ/mol
The net energy gained by a complex through the preferential occupation of lower-energy d orbitals.
CFSE = (−0.4n_t2g + 0.6n_eg)Δ₀
Crystal Field Theory
Inorganic & Coordination Chemistry
kJ/mol
The model treating metal–ligand bonding as purely electrostatic and analysing how ligand fields split the metal d orbitals.
Crystal Lattice
Chemical Bonding & Molecular Structure
Dimensionless
The regular, repeating three-dimensional arrangement of particles in a crystalline solid.
Crystalline Solid
States of Matter & Gas Laws
Dimensionless
A solid in which the constituent particles are arranged in a regular, repeating three-dimensional pattern extending over long distances.
Crystallisation
Foundations of Chemistry
Dimensionless
A purification technique in which a solid is separated from solution as an ordered crystalline lattice.
Curie
Nuclear & Radiochemistry
Ci
The older unit of radioactivity, defined as the activity of one gram of radium-226.
1 Ci = 3.7 × 10¹⁰ Bq
Cyclic Process
Thermochemistry & Thermodynamics
J
A process in which a system undergoes a series of changes and returns to its exact initial state.
ΔU = 0, q = −w
d-Block Elements
Atomic Structure & Periodicity
Dimensionless
The elements of groups 3 to 12, whose valence electrons fill d orbitals of the penultimate shell.
(n−1)d¹⁻¹⁰ ns⁰⁻²
Dalton's Atomic Theory
Foundations of Chemistry
Dimensionless
The 1808 model proposing that elements consist of indivisible atoms that are identical within an element and combine in fixed whole-number ratios.
Dalton's Law of Partial Pressures
States of Matter & Gas Laws
Pa
The total pressure of a gas mixture equals the sum of the pressures each component would exert alone in the same volume.
p_total = p₁ + p₂ + p₃ …
Daniell Cell
Electrochemistry & Redox
V
The classic galvanic cell consisting of a zinc electrode in zinc sulfate and a copper electrode in copper sulfate.
Zn + Cu²⁺ → Zn²⁺ + Cu, E° = 1.10 V
de Broglie Relation
Atomic Structure & Periodicity
m
The relation stating that every particle has an associated wavelength inversely proportional to its momentum.
λ = h / mv
Debye–Hückel Limiting Law
Chemical Equilibrium
Dimensionless
The theoretical relation predicting activity coefficients of ions in very dilute solution from their charge and the ionic strength.
log γ = −A z² √I
Decantation
Foundations of Chemistry
Dimensionless
The separation of a liquid from a settled solid or a denser immiscible liquid by carefully pouring off the upper layer.
Decay Constant
Nuclear & Radiochemistry
s⁻¹
The probability per unit time that a given nucleus will decay.
λ = 0.693 / t½
Decomposition Potential
Electrochemistry & Redox
V
The minimum voltage that must be applied to an electrolytic cell before continuous electrolysis begins.
Decomposition Reaction
Stoichiometry & Chemical Reactions
Dimensionless
A reaction in which a single compound breaks down into two or more simpler substances.
AB → A + B
Degenerate Orbitals
Atomic Structure & Periodicity
Dimensionless
Two or more orbitals in the same atom that have exactly the same energy.
Degree of Dissociation
Chemical Equilibrium
Dimensionless
The fraction of the original substance that has broken apart at equilibrium.
α = amount dissociated / initial amount