EFFECT OF ADDED AMMONIA ON THE REACTIONS OF ACTIVE NITROGEN WITH CH4, C2H6, AND C2H4

1962 ◽  
Vol 40 (7) ◽  
pp. 1291-1295 ◽  
Author(s):  
A. N. Wright ◽  
C. A. Winkler
Keyword(s):  
Nitrogen Molecule ◽  
Reaction Vessel ◽  
Active Nitrogen ◽  
Flame Emission ◽  
Excited Nitrogen

The small HCN yield from the CH4 and C2H6 reactions in an unheated, cylindrical reaction vessel is greatly reduced in the presence of added NH3. The addition of NH3 completely quenches the flame emission from the CH4 reaction, and greatly reduces that from the C2H6 and C2H4 reactions. Both flame emission and HCN production from the CH4 and C2H6 reactions appear to be initiated, at reaction temperatures of about 83 °C, by an excited nitrogen molecule similar to that responsible for NH3 decomposition.

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.

scholarly journals An application of the Stern-Gerlach experiment to the study of active nitrogen

1930 ◽  
Vol 127 (806) ◽  
pp. 678-689 ◽  
Keyword(s):  
Dissociation Energy ◽  
Ground State ◽  
Excited Molecule ◽  
Nitrogen Molecule ◽  
Triple Collision ◽  
Chemical Activity ◽  
Active Nitrogen ◽  
Excited Nitrogen ◽  
Energy Relations ◽  
Normal Nitrogen

Many theories have been put forward at one time or another to explain the chemical activity of “active nitrogen” and the mechanism of the production of the yellow “after-glow.” Reunion of nitrogen atoms to form molecules, metastable molecules and interactions between atoms and molecules have all been drawn upon to explain the after-glow. At the time the work described in the present paper was commenced the theory holding the field was that of Sponer. According to this theory two normal nitrogen atoms collide in a triple collision with a normal nitrogen molecule with the resultant formation of one normal nitrogen molecule and one excited molecule. Since the carrier of the after-glow is known to be an excited nitrogen molecule with about 11⋅5 volts energy, and since the dissociation energy was then believed to be 11⋅5 volts, the theory seemed to explain the energy relations of active nitrogen satisfactorily. The comparative rareness of such a triple collision was in agreement with the long life of the after-glow. On this theory the chemical activity would be attributed to the nitrogen atoms (in their ground state). A support for this theory would have been obtained if it could have been shown that nitrogen atoms in their ground state, which is known to be a 4 S state, are present in active nitrogen. Later work has, however, shown that the dissociation energy of the nitrogen molecule is about 9⋅1 volts and not 11⋅5 volts as supposed by Sponer, and hence the theory cannot be valid.

Vacuum ultraviolet chemiluminescence from the reactions of active nitrogen with I2, IBr, ICI, and ICN

1968 ◽  
Vol 46 (8) ◽  
pp. 1429-1434 ◽  
Author(s):  
L. F. Phillips
Keyword(s):  
Energy Transfer ◽  
Emission Intensity ◽  
Vacuum Ultraviolet ◽  
Nitrogen Molecule ◽  
Emission Lines ◽  
Kcal Mole ◽  
Active Nitrogen ◽  
Excitation Mechanisms ◽  
Excited Nitrogen ◽  
Cl Atoms

Numerous emission lines from excited I, Br, and Cl atoms have been observed between 1261 and 2062 Å. For the flames with I2, IBr, and ICl it is possible to assign excitation mechanisms on the basis of the dependence of emission intensity on either [N] or [N]2. In the case of dependence on [N] the emission is the result of energy transfer from an excited nitrogen molecule, which is produced by reaction of N with NI, has an energy of 185 ± 3.5 kcal/mole, and is identified with the predicted 3Δu species. The dissociation energy of NI is found to lie between 35.6 and 40 + 3.5 kcal/mole. It is proposed that excited nitrogen molecules can be produced as well as removed very rapidly by processes of the type[Formula: see text]

THE STUDY OF VIBRATIONALLY EXCITED N2 MOLECULES WITH THE AID OF AN ISOTHERMAL CALORIMETER

1963 ◽  
Vol 41 (4) ◽  
pp. 903-912 ◽  
Author(s):  
J. E. Morgan ◽  
H. I. Schiff
Keyword(s):  
Microwave Discharge ◽  
Reaction Vessel ◽  
Kcal Mole ◽  
Collision Efficiency ◽  
Vibrationally Excited ◽  
Active Nitrogen ◽  
First Case ◽  
Nitrogen Stream ◽  
Excited Nitrogen ◽  
Isothermal Calorimeter

Vibrationally excited nitrogen molecules produced both by a microwave discharge in nitrogen and also by the reaction[Formula: see text]have been examined using an isothermal calorimetric probe.In the first case the energy associated with an 'active' nitrogen stream, due to vibrationally excited N2, was found to be 6.03 kcal mole−1 of total nitrogen. The subsequent relaxation of this species was found to occur almost entirely on the walls of the reaction vessel, with a collision efficiency of 4.5 × 10−4. The addition of other gases greatly accelerated the homogeneous relaxation rate. Collisional efficiencies of N2O, CO2, and Ar were found to be 0.8 × l0−4, 2.3 × 10−5, and 1.0 × 10−6 respectively.The vibrationally excited nitrogen produced by the N/NO reaction was found to possess 20 ± 4 kcal mole−1 of energy compared with the maximum of 75 kcal mole−1 allowed by the exothermicity of the reaction.

Excited nitrogen molecule formation in a DC-glow-discharge-pumped excimer lamp

2001 ◽  
Vol 27 (5) ◽  
pp. 354-355
Author(s):  
A. K. Shuaibov ◽  
L. L. Shimon ◽  
A. I. Dashchenko ◽  
I. V. Shevera
Keyword(s):  
Glow Discharge ◽  
Nitrogen Molecule ◽  
Dc Glow Discharge ◽  
Excimer Lamp ◽  
Molecule Formation ◽  
Excited Nitrogen

scholarly journals Quantum analysis of the rotational structure of the first positive bands of nitrogen (N 2 )

1932 ◽  
Vol 136 (829) ◽  
pp. 114-144 ◽  
Keyword(s):  
Electronic Configuration ◽  
Selective Excitation ◽  
Nitrogen Molecule ◽  
Rotational Structure ◽  
Positive System ◽  
Initial State ◽  
Final State ◽  
Active Nitrogen ◽  
Quantum Analysis ◽  
Vibrational Levels

The greenish-yellow afterglow of active nitrogen was first described, by Lewis. Two decades have passed since Fowler and Strutt showed that this afterglow was due to a selective excitation of a few green, yellow and red bands belonging to the first positive system of the nitrogen molecule (N 2 ). Recent work on active nitrogen indicates that the selective excitation is due to metastable nitrogen atoms giving up their energy to metastable nitrogen molecules in state A, the final state of the first positive bands, thus leading to the selective excitation of certain specific vibrational levels in state B, the initial state of the first positive bands. The molecule then returns to state A, at the same time emitting the bands which constitute the afterglow. From the rotational analysis of the second positive nitrogen bands by Lindau, and Hulthèn and Johansson, it is known that state B corresponds to a 3 II state, the second positive bands having their final state in common with the initial state of the first positive bands. No definite information has been found concerning the electronic configuration of the nitrogen molecule which gives rise to state A. This can be obtained by making a detailed analysis of the rotational structure of the first positive nitrogen bands.

INTENSITIES OF EMISSION LINES IN FLAMES OF METAL HALIDES WITH ACTIVE NITROGEN

1963 ◽  
Vol 41 (8) ◽  
pp. 2060-2066 ◽  
Author(s):  
L. F. Phillips
Keyword(s):  
Energy Transfer ◽  
Energy Transfer Process ◽  
Nitrogen Molecule ◽  
Spectral Lines ◽  
Emission Lines ◽  
Metal Halides ◽  
Kcal Mole ◽  
Active Nitrogen ◽  
Atom Concentration ◽  
Excitation Mechanisms

The intensities of spectral lines emitted by flames of a number of metal halides with active nitrogen have been found to vary as the square of the nitrogen atom concentration. When the total energy required for simultaneous dissociation of the halide and excitation of the metal atom is less than about 200 kcal/mole the energy transfer process is too efficient to be attributed to the termolecular reaction of a halide molecule with a pair of nitrogen atoms. The observations are consistent with the hypothesis that in this case energy is transferred to the halide molecule during collision with a nitrogen molecule in the 5Σg+ state. Possible excitation mechanisms are discussed for less intense lines which would require up to 276 kcal/mole for simultaneous dissociation and excitation.

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