12034-12-7Relevant articles and documents
Kinetic Study of the Na + O2 + He Reaction in the Temperature Range 392-777 K
Vinckler, Chris,Dumoulin, An,De Jaegere, Stephan
, p. 1075 - 1082 (1991)
A kinetic study of the reaction Na + O2 + He -> NaO2 + He has been carried out in a fast-flow reactor in the temperature and pressure ranges of, respectively, 392-777 K and 4-14 Torr.Sodium atoms are generated either by thermal evaporation of sodium metal or by the technique of microwave-induced plasma afterglow atomization.Atomic absorption spectroscopy is used as the detection technique for atomic sodium.A fit of k2 to the expression A(T/300)n yields k2 = (8.6 +/- 0.7)*10-31 (T/300)-1.04 +/- 0.16 cm6 molecule-2 s-1.This rate expression will be compared with kinetic data derived for the above reaction on the basis of time-resolved flash photolysis and excimer laser photolysis measurements.Using the Troe formalism, values of k2 are calculated in the temperature range 200-2000 K and the importance of the reaction in the burnt-gas region of oxygen-rich flames is discussed.
Schechter, W. H.,Sisler, H. H.,Kleinberg, J.
, p. 267 - 269 (1948)
Mass spectrum and sublimation pressure of sodium oxide vapor: Stability of the superoxide molecule NaO2
Hildenbrand, D. L.,Lau, K. H.
, p. 4076 - 4081 (1993)
The total sublimation pressure of Na2O(c) has been measured in the range 1000-1050 K by the torsion-effusion method, and the mass spectra of vapors over Na2O(c) and Na2O2(c) have been examined in order to resolve several issues regarding the thermochemical stability of the superoxide molecule NaO2.Measured torsion-effusion pressures are completely consistent with the primary sublimation process Na2O(c) = 2Na(g) + 0.5 O2(g) and set an upper limit of 200 kJ mol-1 for the bond strength D0(Na-O2).The ionization efficiency curves of Na+ and O2+ in the mass spectrumof vapor over Na2O(c) show no evidence for fragmentation contributions from NaO2.In addition, the absence of a detectable Na+/NaO2 fragment ion signal in vapor over Na2O2(c) can be used to derive an even tighter upper bound of 180 kJ mol-1 for D0(Na-O2).These results are in conflict with various kinetic analyses yielding D0(Na-O2) values of 202 to 243 kJ mol-1, but are in accord with rigorous theoretical calculations giving values near 160 kJ mol-1.
Holt, W.,Sims, W. E.
, p. 432 - 444 (1894)
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Chu,Weismann
, p. 23,24 (1956)
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Chemical kinetics of the NaO (A2∑+) + O(3P) reaction
Griffin,Worsnop,Brown,Kolb,Herschbach
, p. 1643 - 1648 (2001)
Recent evidence has shown that the mesospheric sodium nightglow, a chemiluminescent process which produces atomic sodium D-line radiation in the Earth's upper atmosphere, proceeds through the first excited (A 2∑+) electronic state of NaO. The rate of D-line radiation production is proportional to the rate constant for the reaction of NaO(A 2∑+) + O(3P) and its branching ratio to produce excited Na(2P) rather than ground-state Na(2S). The only previously published measurement of the NaO + O(3P) reaction rate and branching ratio was performed under slow flow conditions and almost certainly primarily represents the reaction of groundstate NaO (X 2∏). We present low-pressure measurements of the NaO + O reaction kinetics using an NaO source reaction known to produce NaO in the (A 2∑+) state and determine the 290 K reaction rate constant to be (5.1 ± 1.8) × 10-10 cm3 s-1 and the branching ratio to produce Na(2P) to be 0.14 0.04. New data on the termolecular rate coefficient for the reaction Na + O2 + He → NaO2 + He at 290 K are also presented.
Schechter, W. H.,Thompson, J. K.,Kleinberg, J.
, p. 1816 - 1818 (1949)
Solvent-Mediated Control of the Electrochemical Discharge Products of Non-Aqueous Sodium–Oxygen Electrochemistry
Aldous, Iain M.,Hardwick, Laurence J.
, p. 8254 - 8257 (2016)
The reduction of dioxygen in the presence of sodium cations can be tuned to give either sodium superoxide or sodium peroxide discharge products at the electrode surface. Control of the mechanistic direction of these processes may enhance the ability to tailor the energy density of sodium–oxygen batteries (NaO2: 1071 Wh kg?1and Na2O2: 1505 Wh kg?1). Through spectroelectrochemical analysis of a range of non-aqueous solvents, we describe the dependence of these processes on the electrolyte solvent and subsequent interactions formed between Na+and O2 ?. The solvents ability to form and remove [Na+-O2 ?]adsbased on Gutmann donor number influences the final discharge product and mechanism of the cell. Utilizing surface-enhanced Raman spectroscopy and electrochemical techniques, we demonstrate an analysis of the response of Na-O2cell chemistry with sulfoxide, amide, ether, and nitrile electrolyte solvents.
Gas-Phase Reaction Rate of Sodium Superoxide with Hydrochloric Acid
Silver, Joel A.,Kolb, Charles E.
, p. 3267 - 3269 (1986)
Metal compounds originating from meteor ablation may provide an additional mechanism for the release of free chlorine from HCl in the stratosphere.For the alkali metals, and sodium in particular, catalytic chemical pathways have been postulated that describe these processes.A critical step in this mechanism is the reaction of NaO2 with HCl.The rate constant for this reaction has been measured in a fast-flow reactor at 295 K and found to be (2.3 +/- 0.4)*E-10 cm3 molecule-1 s-1.The implication of this result on stratospheric ozone chemistry is discussed.
Kinetic Study of the Reactions Na + O2 + N2 and Na + N2O over Extended Temperature Range
Plane, John M. C.,Rajasekhar, B.
, p. 3135 - 3140 (1989)
An investigation is presented of the recombination reaction Na + O2 + N2 by the technique of pulsed photolysis of a Na atom precursor followed by time-resolved laser induced fluorescence spectroscopy of Na atoms at λ = 589 nm.Termolecular behavior was dem