Title: mass-average velocity
Long Title: IUPAC Gold Book - mass-average velocity
DOI: 10.1351/goldbook.M03711
Status: current

Definition
Mass-average velocity: \[\nu_{b} = \rho ^{-1}\ \sum C_{i}M_{i}\nu_{i}\] Cf. molar average velocity: \[\nu_{m} = c_{t}^{-1}\ \sum c_{i}\nu_{i}\] with \(c_{t}=\sum c_{i}\) where \(M_{i}\) = molar mass, \(c_{t}\) = total concentration (\(\pu{mol m-1}\)), \(\rho \) = density of the solution (\(\pu{kg m-3}\)).

Source
- PAC, 1981, 53, 1827. 'Nomenclature for transport phenomena in electrolytic systems' on page 1831 (https://doi.org/10.1351/pac198153101827)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/M03711/html
- json: https://goldbook.iupac.org/terms/view/M03711/json
- xml: https://goldbook.iupac.org/terms/view/M03711/xml

Citation: Citation: 'mass-average velocity' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.M03711
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Accessed: 2025-11-13T13:15:47+00:00