Term: mass distribution ratio
https://doi.org/10.1351/goldbook.M03718

Definition:
The fraction (1- R) of a component in the stationary phase divided by the fraction (R) in the mobile phase: \[D_{\text{m}}=\frac{\text{amount of substance in the stationary phase}}{\text{amount of component in the mobile phase}}\] This term is recommended in preference to the term capacity factor frequently used in the chromatographic literature.

Related Terms:
1) extraction factor (http://doi.org/10.1351/goldbook.E02305).

Source: Orange Book, 2nd ed., p. 107 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'mass distribution ratio' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03718

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