In experiment C1.4.2.2, a dropping funnel is used and the solid is introduced into the flask. The reaction is controlled here by adding drops of a liquid and the gas can be drawn off via the stopcock on the side. In the production of oxygen, for example, hydrogen peroxide is dripped onto the catalyst manganese dioxide and decomposes into water and oxygen.

This variant can be used to produce several other gases, including: O2, NH3, Cl2, HCl, SO2, NO2, CO, C2H2 and CH4.