Composition of the gas evolved by Lunge nitrometer method

Studies on the determination of nitogen in nitrocellulose and nitric acid. III

Abstract

By cooling with liquid oxygen, nitric oxide evolved from the Lunge nitrometer was separated into condensed and in-condensed portions. The condensed portion was further separated into two portions; by vaporization at -130°C leaving an in-condensed portion. These three portions were then used as the sample for the mass spectrometry and the composition was determined.
0.20% nitrogen was found in the gas when both 94.5% and 98% sulfuric acid were used, and these N₂/Ar atios corresponded with that of the sulfuric acid in which nitrogen and argon had been previously dissolved. Judging from this, the nitrogen cannot be formed due to the reaction in the nitrometer but rather is caused by the evolution of the nitrogen dissolved in the sulfuric acid. On the other hand nitrous oxide was a by-product produced by the reaction in the nitrometer. The formation of nitrous oxide was 0.22% when 94.5% sulfuric acid was used, and 0.39% when 98% sulfuric acid was used; the more concentrated sulfuric acid was used, when the more vigorously this side reaction occurred. The same result was obtained when the sample was potassium nitrate. Nitrocellulose samples gave about 0.17% carbon dioxide when either 94.5% or 98% sulfuric acid was used. The percentage of carbon monoxide evolved was 0.02% when 94.5% sulfuric acid was used, and was 0.24% when 98% acid was used; potassium nitrate samples showed a difference in that they yielded no carbon dioxide cr carbon monoxide.