Title: relative viscosity
Long Title: IUPAC Gold Book - relative viscosity
DOI: 10.1351/goldbook.R05282
Status: current

Definition
The ratio of the viscosity of the solution, \(\eta \), to the viscosity of the solvent, \(\eta _{\rm{s}}\), i.e. \(\eta _{\rm{r}} = \frac{\eta}{\eta _{\rm{s}}}\). Synonymous with viscosity ratio.

Related Term
- viscosity: https://goldbook.iupac.org//terms/view/V06627

Source
- Purple Book, 1st ed., p. 62 (http://old.iupac.org/publications/books/author/metanomski.html)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/R05282/html
- json: https://goldbook.iupac.org/terms/view/R05282/json
- xml: https://goldbook.iupac.org/terms/view/R05282/xml

Citation: Citation: 'relative viscosity' 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.R05282
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Accessed: 2026-04-27T18:04:46+00:00