Shock-initiated exothermic reactions. I. The decomposition of nitrous oxide

Abstract

Measurements of the speeds of reflected shocks in mixtures of nitrous oxide- argon (6:94) were made using thin film detectors for timing purposes. Initial temperatures behind the reflected shocks were between 1670 and 1920°K and pressures were in the range 3-4 atm. The results indicate that at lower temperatures the initial endothermic decomposition caused the shock to decelerate. At higher temperatures, fast exothermic reactions rapidly accelerated the shock. Measured shock speeds were thus average values. Consideration must be given, therefore, to the degree of dilution by inert gas and the positions of timing stations and windows relative to the end plate. This is illustrated by reference to previous investigations of the rate constant for the decomposition of nitrous oxide.