The Heat of Formation of Molecular Oxygen

An apparatus has been constructed and described for the production of atomic oxygen and the direct determination of the heat of formation of molecular oxygen. A series of determinations have been conducted in the pressure range of 0.1 to 0.55 mm of mercury. The heat of formation of molecular oxygen was determined by these experiments as 131,000 (\ifmmode\pm\else\textpm\fi{}6,000) calories or 5.7 (\ifmmode\pm\else\textpm\fi{}0.3) volts per gram molecular weight. Several of the properties of atomic oxygen have been investigated including the possibility of long-lived metastable states.