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960 terms · page 27 of 40
Nuclear Stability
The tendency of a nucleus to persist without undergoing radioactive decay.
Biochemistry & Polymer ChemistryNucleic Acid
A biopolymer of nucleotides that stores and transmits genetic information.
Organic ChemistryNucleophile
An electron-rich species that donates a pair of electrons to form a new covalent bond.
Organic ChemistryNucleophilic Substitution
A reaction in which a nucleophile replaces a leaving group attached to a saturated carbon.
Biochemistry & Polymer ChemistryNucleotide
The monomer of nucleic acids, consisting of a nitrogenous base, a five-carbon sugar and a phosphate group.
Atomic Structure & PeriodicityNucleus
The dense, positively charged core of an atom, containing virtually all of its mass in protons and neutrons.
Nuclear & RadiochemistryNuclide
A distinct species of atom characterised by a specific number of protons and neutrons in its nucleus.
Chemical Bonding & Molecular StructureOctahedral Geometry
A shape with six bonded atoms at the vertices of a regular octahedron, all bond angles being 90° or 180°.
Inorganic & Coordination ChemistryOctahedral Splitting
The division of the five d orbitals into a lower t₂g set of three and an upper e_g set of two under an octahedral ligand field.
Chemical Bonding & Molecular StructureOctet Rule
The observation that atoms tend to gain, lose or share electrons until they are surrounded by eight valence electrons.
Chemical Bonding & Molecular StructureOdd-Electron Molecule
A species containing an unpaired electron, so that its total electron count is odd and no octet structure is possible.
Thermochemistry & ThermodynamicsOpen System
A system that can exchange both energy and matter with its surroundings.
Organic ChemistryOptical Activity
The ability of a substance to rotate the plane of polarised light passing through it.
Organic ChemistryOptical Isomerism
Stereoisomerism in which molecules are non-superimposable mirror images and rotate plane-polarised light in opposite directions.
Inorganic & Coordination ChemistryOptical Isomerism in Complexes
The existence of non-superimposable mirror-image forms of a coordination compound.
Chemical EquilibriumOptimum Conditions for Industrial Yield
The compromise set of temperature, pressure and catalyst chosen to balance equilibrium yield against reaction rate and cost.
Chemical Kinetics & CatalysisOrder of Reaction
The power to which the concentration of a given reactant is raised in the experimentally determined rate law.
Inorganic & Coordination ChemistryOre
A naturally occurring mineral deposit from which a metal can be extracted profitably.
Organic ChemistryOrganic Chemistry
The study of the structure, properties, composition and reactions of carbon-containing compounds.
Inorganic & Coordination ChemistryOrganometallic Compound
A compound containing at least one direct bond between a metal and a carbon atom.
Solutions & Colligative PropertiesOsmosis
The net movement of solvent molecules through a semipermeable membrane from a dilute to a concentrated solution.
Solutions & Colligative PropertiesOsmotic Pressure
The external pressure that must be applied to a solution to prevent the inward flow of solvent through a semipermeable membrane.
Acids, Bases & SaltsOstwald's Dilution Law
The relation showing how the degree of ionisation of a weak electrolyte increases on dilution.
Analytical Chemistry & SpectroscopyOutlier Test
A statistical procedure for deciding whether a suspect result differs enough from the others to be rejected.