The flame spectrum of carbon monoxide III. The cool flame

Abstract

The spectra of the cool flames, or pre-ignition glows, of carbon monoxide with oxygen and with nitrous oxide have been photographed. The cool flame shows the same faintly banded spectrum as the normal flame, but this band structure is more clearly developed. The OH bands are absent from the cool flame, which, however, shows strong sodium emission. Cuprous chloride appears very readily as an impurity and the band systems of CuCl show a markedly different intensity distribution in the cool flames with oxygen and with nitrous oxide. The application of the results to the theory of the combustion mechanism is briefly discussed.