1 / VOL. 1, NO. 4 ISSN 1430-4171 THE CHEMICAL EDUCATOR http://journals.springer-ny.com/chedr © 1996 SPRINGER-VERLAG NEW YORK, INC. 10.1007/s00897960045a Laboratories and Demonstrations Demonstrating Catalysis with a Bang! GREG OWENS and THOMAS G. RICHMOND* Department of Chemistry University of Utah Salt Lake City, Utah 84112 richmond@chemistry.utah.edu The addition of 5% Pd/C provides a novel means of initiating the dramatic reaction between hydrogen and oxygen gases. simple yet highly effective means of demonstrating the use of a standard Pd/C hydrogenation catalyst to initiate the explosive reaction of hydrogen and oxygen gases is reported. Addition of approximately 30 mg of 5% Pd/C to a one-liter plastic soda bottle containing a 1:1 hydrogen and oxygen mixture results in, after a brief induction period, a dramatic explosion that is louder than that of a similar mixture initiated by a flame. Introduction Catalysis is pervasive in modern chemistry [1], but only a few demonstrations are available to illustrate this important concept. Most involve reactions of hydrogen peroxide or metal- catalyzed oxidation reactions of NH 3 or alcohols [2]. It has been said that hydrogen and oxygen can be used to illustrate all the principles of chemistry [3]. The well-known explosive reaction of hydrogen and oxygen gases initiated by a flame is an effective and often used demonstration in introductory A