The Effect of Pressure on the Rate of Decomposition of Potassium Chlorate-Manganese Dioxide Mixtures

It has been believed that pressure has no effect on the rate of decomposition of potassium chlorate. At 125° oxygen is evolved from a mixture of MnO2: KClO3:: 1: 2 if the pressure is below 0.1 mm. of mercury but not at atmospheric pressure. At 175° oxygen is evolved from the same mixture at 2-3 mm. pressure of mercury but not at atmospheric pressure. At 300° the same mixture decomposes almost explosively at atmospheric pressure but will remain 90% undecomposed after seven hours at 320° if the pressure is above 300 atmospheres