Determination of Hydrogen‐Atom Concentration by Lyman‐α Photometry. I. Oscillator Strength of the Hydrogen‐Atom 2P32,12←2S12 Transition. II. Kinetics of the Reaction of Hydrogen Atoms with Acetylene and Ethylene

1966 ◽  
Vol 45 (10) ◽  
pp. 3632-3641 ◽  
Author(s):  
Joe V. Michael ◽  
Ralph E. Weston
Keyword(s):  
Hydrogen Atom ◽  
Oscillator Strength ◽  
Hydrogen Atoms ◽  
Atom Concentration ◽  
Kinetics Of

scholarly journals The kinetics of the interaction of atomic hydrogen with olefines II. Diffusion theory

1949 ◽  
Vol 196 (1047) ◽  
pp. 466-478 ◽  
Keyword(s):  
Hydrogen Atom ◽  
Gas Phase ◽  
Diffusion Theory ◽  
One Dimension ◽  
Hydrogen Atoms ◽  
Collision Efficiency ◽  
Atom Concentration ◽  
Differential Diffusion ◽  
Set Up ◽  
Kinetics Of

In this paper, a system is described in which diffusion of a hydrogen atom takes place effectively in one dimension. The exact differential diffusion equations can be set up and solved, taking into account the possibility of gas-phase removal of the hydrogen atom by a reaction such as H + C 2 H 4 = C 2 H 5 . The collision efficiency of such a reaction has been related to the fraction of hydrogen atoms which reach the oxide layer under certain well-defined conditions. The calculated distribution curves of hydrogen atom concentration throughout the reaction vessel are also given under various conditions.

scholarly journals The photolysis of ammonia

1940 ◽  
Vol 175 (961) ◽  
pp. 187-207 ◽  
Keyword(s):  
Hydrogen Atom ◽  
Preceding Paper ◽  
Ammonia Molecule ◽  
Experimental Techniques ◽  
Hydrogen Atoms ◽  
Atom Concentration ◽  
Important Discrepancy

It has been shown in the preceding paper that the hypothesis that hydrazine is responsible for the anomalously low hydrogen atom concentration in the decomposition of ammonia must be abandoned. In order to explain this important discrepancy some new experimental techniques require to be developed which will settle the matter without appeal to further hypotheses. There are two general explanations of the discrepancy: (1) the hydrogen atoms are not produced as fast as that calculated on the assumption that every ammonia molecule absorbing a quantum necessarily decomposes, (2) that some entity not yet recognized removes hydrogen atoms at a rate faster than that at which they normally recombine. In this paper methods will be described in which these two problems are solved, and finally there is a discussion of the photochemistry of ammonia in the light of the new results obtained during these experiments.

Determination of the Rates of Hydrogen Atom Reaction with NO by a Modulation Technique

1973 ◽  
Vol 51 (3) ◽  
pp. 370-372 ◽  
Author(s):  
R. Atkinson ◽  
R. J. Cvetanović
Keyword(s):  
Nitric Oxide ◽  
Hydrogen Atom ◽  
Phase Shift ◽  
Rate Constants ◽  
Hydrogen Atoms ◽  
Arrhenius Parameters ◽  
Modulation Technique ◽  
The Absolute

A modulation technique has been used to determine from phase shift measurements the absolute values of the rate constants and the Arrhenius parameters of the reaction of hydrogen atoms with nitric oxide.

II.—The Van der Waals Force between a Proton and a Hydrogen Atom

1941 ◽  
Vol 61 (1) ◽  
pp. 20-25 ◽  
Author(s):  
C. A. Coulson
Keyword(s):  
Hydrogen Atom ◽  
Power Series ◽  
Interaction Energy ◽  
Van Der Waals ◽  
Ground States ◽  
Van Der Waals Forces ◽  
Van Der Waals Force ◽  
Hydrogen Atoms ◽  
Nuclear Separation

The calculation of Van der Waals forces has acquired considerable interest recently through the work of Buckingham, Knipp and others (Buckingham, 1937; Knipp, 1939). In these papers the interaction energy between two atoms is expressed as a power series in i/R, where R is the nuclear separation, and the various terms in this series are known as dipole-dipole, dipole-quadrupole, quadrupole-quadrupole, etc… interactions. In most cases only approximate values are obtainable for the coefficients in this series, though for two hydrogen atoms in their ground states, Pauling and Beach (1935) have determined the magnitudes correct to about I in 106. In this paper we discuss the simplest possible problem of this nature, i.e. the force between a bare proton and a normal unexcited hydrogen atom. We shall show that a rigorous determination of the coefficients in the power series can be made.

The kinetics of the interaction of atomic hydrogen with olefines. V. Results obtained for a further series of compounds

1950 ◽  
Vol 202 (1069) ◽  
pp. 181-202 ◽  
Keyword(s):  
Double Bond ◽  
Hydrogen Atom ◽  
Atomic Hydrogen ◽  
Methyl Radicals ◽  
Hydrogen Atoms ◽  
Alkyl Radicals ◽  
Kinetics Of ◽  
Interesting Generalization

In this paper the efficiency of interaction of a hydrogen atom with a series of olefines has been determined, the olefines being members of the series obtained by progressively replacing the hydrogen atoms of ethylene by methyl radicals. The interesting generalization which emerges from this is that the efficiency of interaction does not vary very much with the nature of the alkyl substituents in the molecule, and calculations involving the heats of addition of a hydrogen atom to a double bond confirm this generalization. The data presented here are discussed critically in relation to information available on the reaction of CCl 3 radicals with olefines and of alkyl radicals with olefines, complete general agreement being demonstrated.

An accurate determination of the structure of ammonium oxamate

1963 ◽  
Vol 275 (1363) ◽  
pp. 469-491 ◽  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Atom ◽  
Accurate Determination ◽  
Three Dimensional ◽  
Ammonium Ion ◽  
Intensity Data ◽  
Single Bond ◽  
Hydrogen Atoms ◽  
Librational Motion

The crystal structure of ammonium oxamate (CONH 2 .COONH 4 ) has been studied using Cu Ka X-radiation, by means of a three-circle diffractometer incorporating a xenon-filled proportional counter. Accurate three-dimensional intensity data were collected and a least-squares refinement was carried out. The positions of the hydrogen atoms were obtained and refined. A peak of electron density, about half as high as a hydrogen atom, was observed at the centre of the C—C bond and a correction applied for it increased the length of the bond by 0.003 Å. The bond lengths were corrected for librational motion, and the values obtained are C—C =1.564 ±0.002 Å; C—N = 1.324± 0.002 Å; C—O (amidic) = 1.248± 0.002 A; C— O (carboxylate) = 1.257 + 0.003 Å and 1.256 ± 0.003 Å. The oxamate ion is found to be planar, and the ammonium ion tetrahedral. The length of the C—C bond is greater than any theoretical value yet suggested for the length of a single bond between trigonally hybridized carbons atoms.

Mesure de la constante de vitesse de réaction des atomes d'hydrogène sur l'éthane et le propane en réacteurs tubulaire et parfaitement agité ouverts

1978 ◽  
Vol 56 (3) ◽  
pp. 392-401 ◽  
Author(s):  
Jacques Lede ◽  
Jacques Villermaux
Keyword(s):  
Hydrogen Atom ◽  
Rate Constant ◽  
Electrical Discharge ◽  
Room Temperature ◽  
Hydrogen Atoms ◽  
Atom Concentration ◽  
Sensitive Method ◽  
Good Agreement

The rate constant for the reaction of hydrogen atoms, generated by electrical discharge, with ethane and propane has been studied in tubular and perfectly stirred open reactors. Measurements are made with a new and very sensitive method of analysis of the hydrogen atom concentration. The results obtained near room temperature are in good agreement with those of other authors operating at much higher temperatures. The following estimates may be made:[Formula: see text]

scholarly journals The kinetics of the interaction of atomic hydrogen with olefines III. Theory and technique involved in the use of the oxides of molybdenum and tungsten as hydrogen atom removers

1949 ◽  
Vol 196 (1047) ◽  
pp. 479-493 ◽  
Keyword(s):  
Hydrogen Atom ◽  
Molybdenum Oxide ◽  
Atomic Hydrogen ◽  
Colorimetric Method ◽  
Oxide Surface ◽  
Hydrogen Atoms ◽  
Alkyl Radicals ◽  
Kinetics Of ◽  
And Tungsten

The colorimetric method of estimating the rate of addition of hydrogen atoms to the oxides of molybdenum and tungsten is discussed in detail. It is also shown that alkyl radicals are efficiently removed by molybdenum oxide, and allowance is made for the effect of their presence on the blueing rate of the oxide surface. The method of evaluating collision efficiencies from the data obtained is indicated in full, and the construction and operation of a calculator to assist in the computation is described.

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