Title: relative preconcentration Long Title: IUPAC Gold Book - relative preconcentration DOI: 10.1351/goldbook.R05274 Status: current Definition An operation (process) as a result of which the ratio of concentration or amounts of microcomponents and main macrocomponents increases. This is a particular example of a separation, but at greatly differing concentrations of components. The ratio of the masses of the initial and final samples is not of great importance. Frequently, the main purpose of relative preconcentration is the replacement of a matrix unsuitable for analysis by a suitable medium. In some cases, it is difficult to trace a boundary between the absolute and the relative preconcentrations as, for example, in preconcentration by zone melting. Related Terms - melting: https://goldbook.iupac.org//terms/view/M03821 - preconcentration: https://goldbook.iupac.org//terms/view/P04803 Source - PAC, 1979, 51, 1195. 'Separation and Preconcentration of Trace Substances. I-Preconcentration for Inorganic Trace Analysis' on page 1197 (https://doi.org/10.1351/pac197951051195) Other Outputs - html: https://goldbook.iupac.org/terms/view/R05274/html - json: https://goldbook.iupac.org/terms/view/R05274/json - xml: https://goldbook.iupac.org/terms/view/R05274/xml Citation: Citation: 'relative preconcentration' 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.R05274 License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. Collection: If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. Accessed: 2026-04-21T08:23:51+00:00