Photometric Investigations of Alkali Metals in Hydrogen Flame Gases. I. A General Survey of the Use of Resonance Radiation in the Measurement of Atomic Concentrations

摘要: Experiments on the intensity of emitted resonance radiation in various first and second doublets alkali metals have been made hot gases a few centimetres above primary zone combustion hydrogen-oxygen flames diluted with nitrogen, using photoelectric technique. The results confirm that emission is thermal origin lead to several conclusions interest. ( а ) Very low intensities are always obtained lithium, account removal metal by hydroxyl radicals form very stable gaseous hydroxide. This effect decreasingly important caesium potassium, negligible sodium. b reaction give metallic hydroxide appears be thermodynamically equilibrated hotter (> 2000° K), but becomes progressively markedly incomplete towards lower temperatures. c In case only, ionization accounts for substantial fraction total present. Estimation this amount leads conclusion negatively charged OH ¯ ions, as well free electrons, A value electron affinity 65 ± 5 kcal deduced. d Consideration sodium, which not complicated either formation hydroxide, or ionization, shows it possible estimate relative concentration unexcited atoms two-flame technique, absolute sodium flame may measured observation onset self-absorption. e method useful confirmation determination f -values lines.