A MODIFICATION OF THE DEMONSTRATION OF THE OSTWALD PROCESS SAUL S. HAUBEN and RICHARD 8. SfEGEL Brooklyn Technical High School, Brooklyn, New York
IN
catalyst, broken unglazed tile is used, 15 to 20 mesh. A former issue of THIS JOURNAL,^ we described a simple demonstration of the oxidation of ammonia The tile is soaked for several hours in chloroplatinic to nitric acid. Since then we have noticed two defects acid prepared as previously directed.' It is then in this method. It has been difficult to control the ignited in the same manner. After leaving the catalyst tube the air-ammonia amount of ammonia used and the asbestos carrier of the catalyst tended to pack tightly, thus obstructing mixture is drawn into a one-liter Florence flask. When the free flow of gas. We have modified the apparatus the brown fumes of nitrogen dioxide appear in the flask, the flame should be removed. The catalyst as indicated below and as shown in the diagram. Air is drawn through a wide-mouth bottle containing usually begins to glow, indicating the exothermic naa small quantity of 1 : 1 ammonium hydroxide solu- ture of the reaction. I t is suggestedthat a wide-mouth tion. Note that the tubing does not extend into the bottle containing some water be added between the solution. In this manner, ammonia and air in the Florence flask and the aspirator, so that the nitrogen proper proportions are drawn through the catalyst dioxide after being seen is absorbed in the water to n-hich has been strongly heated in a glass tube for about form the nitric acid. It is also advisable, a t the comtwo minutes. Suction is supplied by a water aspirator. pletion of the demonstration, to heat the catalyst Instead of asbestos fibers as a carrier for the platinum strongly for a few minutes while drawing air through. ' H A ~ E NS., S., AND R. 8. SIEOEL,J. CHEM.EDUC.,20, 166 This will remove any adsorbed gases, thus preparing the way for the next demonstration. 1943).
