Ausgangslösung

Ausgangslösung, literally "starting solution," is a term used in German-language scientific literature to designate the solution that serves as the starting point for an experimental procedure, analysis, or synthesis. It identifies the initial composition, concentration, and conditions from which subsequent steps are derived.

In chemistry and analytical chemistry, the Ausgangslösung may be the dissolved reagent prepared for a titration, spectroscopic measurement, or quantitative analysis. It is typically specified by its solvent, concentration (for example molarity), temperature, and sometimes pH or ionic strength. In sample preparation, the Ausgangslösung refers to the solution obtained after dissolving or digesting a solid sample before analysis. It can also denote the product of an initial reaction before purification or dilution.

The term emphasizes the contrast with later stages of the workflow, such as intermediates, collected fractions, or the final solution after completion of processing. Usage is common in German manuals, lab protocols, and scientific papers. In English, the closest equivalents are "starting solution" or "initial solution," though the term is not as widely used as in German.