摘要:

AbstractThe crystal structure of the γ‐modification of sulphur trioxide has been completely determined.The cell is orthohombic, with cell constants a = 12.3 Å, b = 10.7 Å and c = 5.3 Å and contains 12 units of SO3; the X‐ray density is 2.29.The structure is a molecule lattice built up of molecules S3O9; a [001] projection is seen in fig. 7, the atomic positions are given on p. 806, 807.The molecule S3O9contains a puckered (SO)3ring (fig. 4b), in agreement with the latest results of Raman and infrared invest

ISSN:0165-0513    

DOI:10.1002/recl.19410601102

出版商:WILEY‐VCH Verlag    

年代:1941

数据来源: WILEY

摘要:

AbstractThe mobile chlorine atom in 1‐chlor‐2‐nitro‐4‐cyanbenzene was replaced by amines, oxyethylamine, ethylenediamine, hydrazine and methyl

ISSN:0165-0513    

DOI:10.1002/recl.19410601103

出版商:WILEY‐VCH Verlag    

年代:1941

数据来源: WILEY

摘要:

AbstractAn attempt is made to understand the phenomenon of mixing and unmixing of liquids from a simple model of cohesion forces. Since in the heat of mixing it is only the differences of cohesion forces which are important, induction and dispersion forces are neglected in a first approximation, whereas orientation forces are described by assigning to the molecular surfaces positive or negative spots, which eventually tend toward association. The energy of association and solvation depends on the activity of those spots, the entropy on their area. Starting from simple molecular models, the shape of the mixing curve is derived theoretically and in all cases experimentally found examples are quoted. There appears to exist no fundamental miscibility curve, from which all experimentally realised curves could be derived. On the contrary, the theoretical curves differ considerably for different mixtures, even when we assume the liquid state stable to arbitrary high and low temperatures.

ISSN:0165-0513    

DOI:10.1002/recl.19410601104

出版商:WILEY‐VCH Verlag    

年代:1941

数据来源: WILEY

摘要:

AbstractThe solubility of water in CCl4,CHCl3, CH2Cl2, CH3.CHCl2, CH2Cl.CH2Cl, CH2Br.CH2Br, CH3.CCl3, CH2Cl.CHCl2, CHCl2.CHCl2, CH2Cl.CCl3and CHCl2.CCl3has been measured at 0°, 25° and 30° C. From these measurements, together with those of van Arkel and Vles1), and from the theoretical considerations of the foregoing paper, the complete mixing curve has been construct

ISSN:0165-0513    

DOI:10.1002/recl.19410601105

出版商:WILEY‐VCH Verlag    

年代:1941

数据来源: WILEY

摘要:

AbstractThe qualitative results of Levine and Cole on the formation of glyoxal, methyl glyoxal and dimethyl glyoxal in the ozonization of o‐xylene are confirmed. However, we obtained much greater yields of these oxidation products, namely 20‐26% of the theoretical yield.A method has been worked out for determining these aldehydes and ketones in the form of the oximes. The mixture of oximes obtained in the ozonization of o‐xylene consists of 21.0% dimethylglyoxime, 34.2% methylglyoxime and 43.9% glyoxime (averages of 5 experiments).This ratio is in good accordance with the ratio calculated on the basis or the following assumptions:1.that the six CC bonds in the benzene‐nucleus of o‐xylene are equivalent (the two Kékulé structures contributing each for 50% to the structure of o‐xylene);2.that the addition of ozone is not affected by steric hindrance of the methyl groups.The ozonization of 1,2,4‐trimethylbenzene has been investigated by means of the same methods. In this case the mixture of oximes consists of 17.9% dimethylglyoxime, 66.2% methylglyoxime and 14.2% glyoxime (average of two experiments). This ratio agrees very well with the ratio calculated on the basis of the assumptions: 1. that the six CC bounds in the benzenering of 1,2,4‐trimethylbenzene are equivalent, 2. that the addition of ozone is not affected by steric hindra

ISSN:0165-0513    

DOI:10.1002/recl.19410601106

出版商:WILEY‐VCH Verlag    

年代:1941

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19410601108

出版商:WILEY‐VCH Verlag    

年代:1941

数据来源: WILEY

摘要:

AbstractIn the course of a study of a number of physical properties of phosphorus pentabromide, including the determination of the molecular structure of the compound, the vapour pressure of the substance has been measured mainly between 75° and 106° C.In the literature only a few incidental data on the vapour pressure could be found. Prideaux1) made some qualitative measurements between 23° C and 100° C, at which temperature the pressure of about one atmosphere is reached. As the error in his measurements amounts to about 5 cm of mercury, it seemed worth while to repeat them with apparatus more suitable for the required accuracy, and with a sample of phosphorus pentabromide prepared in the laboratory and purified under well defined conditi

ISSN:0165-0513    

DOI:10.1002/recl.19410601109

出版商:WILEY‐VCH Verlag    

年代:1941

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19410601101

出版商:WILEY‐VCH Verlag    

年代:1941

数据来源: WILEY