THE RATE OF REACTION OF ACTIVE NITROGEN WITH AMMONIA AND ETHYLENE

1962 ◽  
Vol 40 (1) ◽  
pp. 5-14 ◽  
Author(s):  
A. N. Wright ◽  
C. A. Winkler
Keyword(s):  
Gas Phase ◽  
Rate Constant ◽  
Reaction Times ◽  
Active Nitrogen ◽  
Atom Concentration ◽  
Initial Flow ◽  
Flow Rates ◽  
Average Value ◽  
Rate Of Reaction ◽  
Excited Nitrogen

The rate constants for the reactions of C2H4 and NH3 are determined by termination of the reactions in the gas phase after different times of reaction. The average value for the rate constant of the N atom–C2H4 reaction at 150 °C is 1.8 × 1010 cc mole−1 sec−1, when the initial N-atom concentration is determined from the maximum production of HCN. The average value for the rate constant for the over-all reaction of NH3 with excited nitrogen molecules, at 104 °C in the "poisoned" system, and 83 °C in the "unpoisoned" system, for low initial flow rates of NH3, or short reaction time, is 2.2 × 1010 cc mole−1 sec−1. The decrease in value of this rate constant at higher initial flow rates of NH3 and longer reaction times in the "poisoned" system indicates that the species responsible for NH3 decomposition is generated during the decay of N atoms in the presence of NH3. The value for the NH3 reaction is discussed in terms of energy transfer.

scholarly journals Reaction of active nitrogen with oxygen

1967 ◽  
Vol 45 (22) ◽  
pp. 2837-2840 ◽  
Author(s):  
A. S. Vlastaras ◽  
C. A. Winkler
Keyword(s):  
Reaction Time ◽  
Oxygen Atom ◽  
Gas Phase ◽  
Rate Constant ◽  
Analytical Method ◽  
Order Rate Constant ◽  
Maximum Amount ◽  
Active Nitrogen ◽  
Tube Reactor ◽  
Different Levels

The maximum yields of oxygen atoms, estimated at different levels in a long-tube reactor by gas-phase "titration" with NO2, were equal for the reactions of active nitrogen with NO and O2. In this reactor, the maximum oxygen-atom production from the oxygen reaction, determined by the amount of N2O3 produced with excess NO2, was found to correspond to the NO "titration" value for the active nitrogen and not to the maximum amount of HCN produced in the active nitrogen – ethylene reaction. A second-order rate constant, [Formula: see text] [Formula: see text]was obtained for the active nitrogen – oxygen reaction.Experiments in a short reactor showed that the validity of the analytical method based on the trapping of N2O3 depended upon adequate reaction time for the NO + NO2 reaction to occur.

THE REACTIVE SPECIES IN ACTIVE NITROGEN

1962 ◽  
Vol 40 (6) ◽  
pp. 1082-1097 ◽  
Author(s):  
A. N. Wright ◽  
R. L. Nelson ◽  
C. A. Winkler
Keyword(s):  
Molecular Nitrogen ◽  
Reaction Vessel ◽  
Active Nitrogen ◽  
Atom Concentration ◽  
Vibrational Levels ◽  
Long Lifetime ◽  
Excited Nitrogen ◽  
A Minor ◽  
Hydrocarbon Reactions ◽  
Decomposition Of No

A study has been made of the discrepancy between the N-atom content of active nitrogen as inferred from the maximum HCN production from the reaction of many hydrocarbons, and that indicated by the extent of NO destruction. The HCN production from several hydrocarbons was similar at high reaction temperatures in a spherical reaction vessel, and was independent of reaction temperature in a cylindrical reaction vessel. The ratio (NO destroyed)/(HCN produced) was found to be independent of the mode of excitation òf the molecular nitrogen and of the N-atom concentration, and to be unaffected by the addition, upstream, of N2O or CO2. Although NH3 was found to be a minor product of the hydrocarbon reactions, HCN accounted for at least 96% of the N-atom content of the products under conditions where its formation is considered a measure of the N-atom concentration. The NO "titration" value, the maximum extent of HCN production from C2H4, and the destruction of NH3 after different times of decay of active nitrogen gave evidence that part of the NO reaction occurred, as does the NH3 reaction, with excited nitrogen molecules. The long lifetime of the N2* species capable of reaction with NO or NH3, as calculated from the above data, strongly favors its identification as low vibrational levels of the N2(A3∑u+) molecule. A consideration of the values for the NO/HCN, NH3/HCN, and NH3/NO ratios, after different times of decay, for poisoned and unpoisoned systems, suggested that the N2* responsible for the NH3 reaction is formed only during homogeneous recombination of N atoms, while the N2* responsible for reaction with NO might be produced by wall recombination as well. Possible reactions of excited molecules present in the active nitrogen – NO system that might lead to decomposition of NO without consumption of N atoms are discussed.

THE RATE OF REACTION OF ACTIVE NITROGEN WITH ETHANE, PROPANE, AND NEOPENTANE

1964 ◽  
Vol 42 (8) ◽  
pp. 1948-1956 ◽  
Author(s):  
W. E. Jones ◽  
C. A. Winkler
Keyword(s):  
Rate Constants ◽  
Reaction Times ◽  
Reactive Species ◽  
Hydrogen Atoms ◽  
Active Nitrogen ◽  
Probe Technique ◽  
Temperature Range ◽  
Excited Species ◽  
Rate Of Reaction ◽  
Dual Activation

The reactions of active nitrogen with ethane, propane, and neopentane have been studied over the temperature range 0 to 450 °C. A cobalt probe technique was used to stop the reactions after various reaction times. Second order rate constants have been calculated on the assumption that nitrogen atoms are the only reactive species in active nitrogen. Broken Arrhenius lines were obtained for both the ethane and neopentane reactions but this behavior was not observed with the propane reaction. The dual activation energies have been attributed to a mechanism involving initiation by both excited molecules and either nitrogen or hydrogen atoms. Methods are outlined by which an estimate has been made of the concentration of excited species assumed to be involved in the ethane reaction.

THE REACTION OF ACTIVE NITROGEN WITH HYDRAZINE

1955 ◽  
Vol 33 (4) ◽  
pp. 692-698 ◽  
Author(s):  
G. R. Freeman ◽  
C. A. Winkler
Keyword(s):  
Hydrogen Cyanide ◽  
Chemical Reactivity ◽  
Large Contribution ◽  
Ammonia Production ◽  
Hydrogen Atoms ◽  
Active Nitrogen ◽  
Flow Rates ◽  
Production Of Hydrogen ◽  
Secondary Reactions ◽  
Excited Nitrogen

Hydrazine was completely destroyed by active nitrogen, at both 150 °C. and 480 °C., up to a hydrazine flow rate of about 22 × 10−6 mole per sec., whereas ammonia production was small at hydrazine flow rates below about 12 × 10−6 mole per sec. Thus it appears that ammonia is formed in secondary reactions only. The results indicate that NH2 radicals rather than hydrogen atoms may be prominent in secondary reactions. Comparison of the rate of hydrazine destruction with the rate of production of hydrogen cyanide from ethylene indicates that excited nitrogen molecules do not make a large contribution to the chemical reactivity of active nitrogen.

THE REACTIONS OF ACTIVE NITROGEN WITH ETHYLENE AND DEUTERATED ETHYLENES

1966 ◽  
Vol 44 (22) ◽  
pp. 2691-2701 ◽  
Author(s):  
Kenneth D. Foster ◽  
P. Kebarle ◽  
H. B. Dunford
Keyword(s):  
Hydrogen Atom ◽  
Mass Spectrometer ◽  
Rate Constant ◽  
Reaction Times ◽  
Order Rate Constant ◽  
Second Order ◽  
Atomic Nitrogen ◽  
Large Excess ◽  
Active Nitrogen ◽  
Initial Concentration

The reaction of active nitrogen with ethylene and deuterated ethylenes has been investigated by use of a mass spectrometer. The rate of disappearance of atomic nitrogen in the presence of ethylene appears to obey the equation[Formula: see text]where kapp is an apparent second order rate constant and [ethylene]0 is the initial concentration of added ethylene. However, exceptions to this equation are found at 0.6 Torr either for short reaction times or for small concentrations of added ethylene, and apparently for short reaction times at 2.6 Torr when a large excess of ethylene is added. Where the above equation is obeyed, kapp = (3 ± 1) × 10−13 cc molecule−1 s−1. The formation of C2D4 in the reaction of active nitrogen with C2D3H is interpreted as further evidence for the importance of hydrogen atom reactions in intermediate steps of the reaction of active nitrogen with ethylene.

CATALYZED RECOMBINATION OF NITROGEN ATOMS, AND THE POSSIBLE PRESENCE OF A SECOND ACTIVE SPECIESIN ACTIVE NITROGEN

1960 ◽  
Vol 38 (12) ◽  
pp. 2514-2522 ◽  
Author(s):  
Roger Kelly ◽  
C. A. Winkler
Keyword(s):  
Rate Constant ◽  
Pressure Range ◽  
Order Rate Constant ◽  
Active Species ◽  
Third Order ◽  
Active Nitrogen ◽  
Atom Concentration ◽  
Order Rate ◽  
Excited Molecules ◽  
Atom Decay

The reactions of ethylene, ethane, and ammonia with active nitrogen have been studied over the pressure range 0.3 to 4 mm usinganunheatedreaction vessel. The object was to determine why each reactant shows, as is well-known, a smaller extent of reaction at lower temperatures than would be predicted from the atom concentration. It was concluded that ethylene probably brought about homogeneouscatalyzedrecombination, i.e. the process [Formula: see text] followed by N + N•C2H4 → N2 + C2H4. The over-all third-order rate constant appeared to be very large, about 1.8 × 10−28 cc2 molecule−2 sec−1. The behavior of ammonia was quite different from that of ethylene and it was, in fact, possible to show that the extent of reaction was not governed by the instantaneous atom concentration at all. The results can be explained qualitatively, however, if it is assumed that excited molecules formed in the course of homogeneous atom decay constitute a second active species in active nitrogen. This view serves also to explain the failure in such work as that of Kistiakowsky etal. to observe ammonia destruction or excited molecules when especially low atom concentrations are used. The few experiments involving ethane were sufficient to show that the reactivity was low for a different reason than with ethylene.

SiF2as a primary desorption product of Si etching by F atoms: Interpretation of laser‐induced fluorescence spectra; rate constant of the gas phase SiF2+F reaction

1991 ◽  
Vol 70 (7) ◽  
pp. 3892-3898 ◽  
Author(s):  
S. Vanhaelemeersch ◽  
J. Van Hoeymissen ◽  
D. Vermeylen ◽  
J. Peeters
Keyword(s):  
Gas Phase ◽  
Rate Constant ◽  
Fluorescence Spectra ◽  
Laser Induced Fluorescence

The Dielectric Discharge as an Efficient Generator of Active Nitrogen for Chemiluminescence and Analysis

1983 ◽  
Vol 37 (6) ◽  
pp. 545-552 ◽  
Author(s):  
John Kishman ◽  
Eric Barish ◽  
Ralph Allen
Keyword(s):  
Gas Phase ◽  
Ground State ◽  
Band System ◽  
Electrothermal Atomization ◽  
Characteristic Radiation ◽  
Gaseous Species ◽  
Vibrationally Excited ◽  
Active Nitrogen ◽  
Excited Species ◽  
Intense Emission

A predominantly blue “active nitrogen” afterglow was generated in pure flowing nitrogen or in air by using a dielectric discharge at pressures from 1 to 20 Torr. The afterglow contains triplet state molecules and vibrationally excited ground state molecules. These species are produced directly by electron impact without the formation and recombination of nitrogen atoms. The most intense emission is the N2 second positive band system. The N2 first positive and N2+ first negative systems are also observed. The spectral and electrical properties of this discharge are discussed in order to establish guidelines for the analytical use of the afterglow for chemiluminescence reactions. The metastatic nitrogen efficiently transfers its energy to atomic and molecular species which are introduced into the gas phase and these excited species emit characteristic radiation. The effects of electrothermal atomization of Zn and the introduction of gaseous species (e.g., NO) on the afterglow are described.

The gas phase reactivity of the dimethylchloronium ion with alkylbenzenes

1981 ◽  
Vol 59 (15) ◽  
pp. 2412-2416 ◽  
Author(s):  
John A. Stone ◽  
Margaret S. Lin ◽  
Jeffrey Varah
Keyword(s):  
High Pressure ◽  
Gas Phase ◽  
Mass Spectrometer ◽  
Aromatic Hydrocarbons ◽  
Relative Rate ◽  
Ion Source ◽  
Nucleophilic Displacement ◽  
Rate Of Reaction ◽  
Displacement Reactions ◽  
Bonded Complexes

The reactivity of the dimethylchloronium ion with a series of aromatic hydrocarbons has been studied in a high pressure mass spectrometer ion source using the technique of reactant ion monitoring. Benzene is unreactive but all others, from toluene to mesitylene, react by CH3+ transfer to yield σ-bonded complexes. The relative rate of reaction increases with increasing exothermicity in line with current theories of nucleophilic displacement reactions.

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