ABSTRACT
The “secret” to maximizing the rate of reaction, and therefore burn rate, for a given pyrotechnic, propellant, or explosive composition can be revealed in a single word—homogeneity. Ideal homogeneity in a solid mixture would be the common proportional distribution and all particles throughout the mixture; that is, all particles are equally blended throughout with no areas of higher or lower concentration. Striking differences in reactivity can result from changes in either of these, as Mr. Guthrie observed with his “fulminating powder.”The actual atmosphere used for a “heat of reaction” experiment can play a critical role in determining the amount of heat that is produced and measured. Experimenters must always be sure to report the atmosphere used in determining any heat output/calorimetric values, to include ambient temperature and pressure. To reproducibly create the desired pyrotechnic effect from a given mixture, the chemist must be aware of the large number of variables that can affect performance.
