Abstract: The laboratory apparatus is used for separating gaseous, liquid and solid substances from gas samples (for example air) to be trace analyzed. It comprises a vessel and a mixer insert with nozzles. The gas fed into the mixer insert emerges from the nozzles at high speed into an absorption liquid held in the vessel so that intensive mixing and hence high absorption of the substances takes place. After passing through the liquid the gas leaves the vessel via an outlet. The substances absorbed in the liquid are available for analysis.