Chemistry terms starting with D

Diastereomer Organic Chemistry Dimensionless A stereoisomer that is not a mirror image of the compound with which it is compared.

Diffusion States of Matter & Gas Laws m²/s The spontaneous spreading of one substance through another as a result of random molecular motion. J = −D (dc/dx)

Dilution Solutions & Colligative Properties mol/L The process of reducing a solution's concentration by adding more solvent, leaving the amount of solute unchanged. M₁V₁ = M₂V₂

Dimensional Analysis Foundations of Chemistry Various A calculation method that tracks and cancels units through a chain of conversion factors to reach the required quantity. given quantity × (desired unit / given unit) = answer

Dipole Moment Chemical Bonding & Molecular Structure D The vector measure of the separation of positive and negative charge in a bond or molecule. μ = q × d

Dipole–Dipole Interaction Chemical Bonding & Molecular Structure kJ/mol The electrostatic attraction between the positive end of one polar molecule and the negative end of another. E ∝ μ₁μ₂ / r³

Diprotic Acid Acids, Bases & Salts mol/L An acid that can donate two protons per molecule. H₂A ⇌ 2H⁺ + A²⁻

Disaccharide Biochemistry & Polymer Chemistry Dimensionless A carbohydrate formed when two monosaccharide units join through a glycosidic bond. C₁₂H₂₂O₁₁

Disproportionation Reaction Stoichiometry & Chemical Reactions Dimensionless A redox reaction in which a single species is simultaneously oxidised and reduced. 2A → A⁺ + A⁻

Dissociation Solutions & Colligative Properties Dimensionless The breaking apart of a solute into two or more particles when it dissolves, increasing the effective particle count. AB → A⁺ + B⁻

Dissociation Constant Chemical Equilibrium mol/L The equilibrium constant for the breaking apart of a compound or complex into smaller species. Kd = [A][B] / [AB]

Dissolution Solutions & Colligative Properties kJ/mol The process by which a solute disperses into a solvent to form a solution.

Distillation Foundations of Chemistry Dimensionless A separation technique that exploits differences in volatility by vaporising a liquid and condensing the vapour in a separate vessel.

Distribution Law Chemical Equilibrium Dimensionless The principle that a solute distributes itself between two immiscible solvents in a constant ratio at fixed temperature. K_D = C_organic / C_aqueous

DNA Biochemistry & Polymer Chemistry Dimensionless The double-stranded nucleic acid that carries the hereditary information of almost all living organisms.

Double Displacement Reaction Stoichiometry & Chemical Reactions Dimensionless A reaction in which two compounds exchange partner ions to form two new compounds. AB + CD → AD + CB

Double Helix Biochemistry & Polymer Chemistry nm The structure of DNA, in which two antiparallel polynucleotide strands wind around a common axis. 10.5 base pairs per turn

Double Salt Acids, Bases & Salts Dimensionless A salt containing two different cations or anions that dissociates completely into all its constituent ions in solution. e.g. K₂SO₄·Al₂(SO₄)₃·24H₂O

Dry Cell Electrochemistry & Redox V A primary cell using a moist paste rather than a liquid electrolyte, so it can be used in any orientation. Zn + 2MnO₂ + 2NH₄⁺ → Zn²⁺ + Mn₂O₃ + 2NH₃ + H₂O

Dynamic Equilibrium Chemical Equilibrium Dimensionless An equilibrium in which opposing processes continue at the molecular level but at equal and opposite rates. rate_forward = rate_reverse

d–d Transition Inorganic & Coordination Chemistry nm The promotion of an electron between split d orbitals, responsible for the characteristic colours of transition metal complexes. ΔE = hν = Δ

Terms starting with D