A SIMPLE SUBSTITUTE FOR A-KIPP GENERATOR -ANK
LANE,
BATESCOLLEGE, LEWIS~N, MA-
It frequently happens that individual gas generators for elementary students are desired. The supply of Kipp generators is usually inadequate. The accompanying diagram illustrates a simple substitute which can be quickly made from the equipment usually present in the elementary locker. Ordinary gas bottles and 4- to 5-mm. tubing serve best. It is a convenient source of hydrogen sulfide for studying the insoluble sulfides. Since it is automatic, it works very well as a source of carbon dioxide in the preparation of sodium bicarbonate by a modified Solvay process. The breather tube B may be led to a sink or waste beaker instead of being left free. The mat M of glass or copper wool is essential to the smooth operation in order to keep the reacting material (marble or iron sulfide) above the lowest level of the acid. The tube S may be varied in length to deliver gas a t different pressures. The actual preparation of the gas and the construction of such an apparatus is far more instructive than using tanks of compressed gas.
