Volume 12, Issue 2, 01 February 1944
Index of content:
12(1944); http://dx.doi.org/10.1063/1.1723906View Description Hide Description
The reaction of hydrogen atoms with nitric oxide has been studied by mercury sensitization of various mixtures of hydrogen and nitric oxide to produce nitrogen and water. The rate at constant nitric oxide pressure is proportional to the hydrogen at low hydrogen pressures, the effect diminishing at higher concentrations. With a given hydrogen concentration nitric oxide is almost without effect until an excess is present when it shows a retardation. At constant total pressure a maximum rate occurs with a particular excess of hydrogen. A mechanism based on HNO radicals has been postulated. These radicals decompose by a wall reaction to give nitrous oxide which is rapidly reduced to nitrogen.
12(1944); http://dx.doi.org/10.1063/1.1723907View Description Hide Description
Raman frequencies, relative intensities, and depolarization factors are given for (A) 2,5‐dimethyl‐1,5‐hexadiene and (B) 2,5‐dimethyl‐2,4‐hexadiene. The relative intensities and depolarization factors were obtained with the aid of a Gaertner microdensitometer. The two molecules are isomers, each containing eight carbon and fourteen hydrogen atoms. (A) contains two XYC=CH2 groups and (B) contains two XXC=CHZ groups. In (B) the double bonds are conjugated, in (A) unconjugated. The results for the five olefinic frequencies are compared with data previously obtained for nine other olefins. The data for the olefinic lines of (A) are 1297(50), 1414(430)0.74, 1651(1000)0.21, 2977(580)0.28, and 3074(220)0.78, values which are in good agreement with those obtained previously for olefins containing an XYC=CH2 group. For (B) the olefinic frequencies are 1227(75)0.46, 1663(1000)0.18, 3012(vw), and 3040(vw) (vw = very weak). The conjugation thus resulted in a lowering of these frequencies of 19, 19, 0, and 10 cm−1, respectively, from the values of the corresponding frequencies of the XYC=CHZ group in dipentene.
The Electrostatic Contribution to Hindered Rotation in Certain Ions and Dipolar Ions in Solution. III12(1944); http://dx.doi.org/10.1063/1.1723908View Description Hide Description
In the present paper we shall extend the previous methods to a relatively complicated molecule, glutamic acid:Other calculations will also be made and an empirical relationship among the effective dielectric constants found in this and earlier papers will be pointed out.
12(1944); http://dx.doi.org/10.1063/1.1723909View Description Hide Description
The photolysis of methylamine has been shown to proceed essentially by two consecutive first‐order reactions, the first to produce hydrogen, ammonia, and CH2 : NCH3; the second a dehydrogenation of the latter at a rate approximately double the first. A mechanism involving hydrogen atoms has been postulated. These have been shown experimentally to be present and also have been shown by discharge‐tube experiments to react with methylamine.
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