British Chemical Abstracts

BRITISH CHEMICAL ABSTRACTS A.-PURE CHEMISTRY DECEMBER, 1928. General, Physical, and Inorganic Chemistry. Ballistic method of ionisation measurement set up by the H, molecule, and not by H3. It is also with a quadrant electrometer. D. L. W e b s t e r concluded that the continuous hydrogen spectrum is and R. M. Y e a t m a n (J. Opt. Soc. Amer., 1928, 17, due to excited hydrogen molecules as suggested by 248—253).—The method of using the quadrant Blackett and Franck (A., 1925, ii, 1097) and not to electrometer by taking the reading when the needle the decomposition of H2+ ions as supposed by Herzberg lias stopped swinging is open to the objection that (this vol., 1). ‘ J. W. S m i t h . the time required is long. The method described is to read the farthest point of swing. The accuracy of Extinction of the Z)-lines in flames by [the the method depends on (1) linearity of the differential addition of] chlorine compounds. J. F r a n c k equation of motion; (2) homogeneity, except for the and G. E. G ib s o n (Z. Physik, 1928, 50, 691).—By term proportional to the ionisation; (3) initial values observing the behaviour of a salted flame to which small amounts of carbon tetrachloride vapour were of deflexion and velocity must be zero; (4) the added it has been shown that a complete parallelism exposure time must be constant. In practice, the exists by the extinction of the emission of the D-lines last can easily be satisfied, whilst (2) and (3) can be satisfied by introducing a constant current opposite and their disappearance in the absorption spectrum. This is held to indicate that the disappearance of the to that of the ionisation chamber. The first condition D-lines is due to the disappearance of the free sodium depends on the instrument. Tests on a Compton atoms which pass under these conditions into sodium electrometer showed that all the conditions could be chloride molecules. J. W. S m i t h . satisfied and that the method has no systematic errors large enough to detect in the presence of a 1 % Spectra of neon, argon, and- krypton (addi erratic error. For large deflexions there is a deviation tional lines). W. G r e m m e r (Z. Physik, 1928, 50, of 1% from linearity, but calibration by means of a 716—724).—A number of new lines in the red and potentiometer enables the comparison of ionisation infra-red regions have been observed in the spectra currents to be carried out accurately. of neon and argon. Most of these have been shown A. J. Me e . to be members of the sp-, ps-, or pd-series. The Proof of Schrodinger's theory. J. L. S n o e k , spectrum of krypton, like those of neon and argon, jun., and L. S. O r n s t e i n (Z. Pliysik, 1928, 50, shows certain constant vibrational differences. These 600—608).—Measurements have been made of the regularities enable a considerable number of the fine structure of the absorption in the Ha and H# spectral lines of krypton to be classified. lines. The ratio of the total absorption of the Ha J. W. S m i t h . line to that of the line is 5-25, a value in good Breadth of some lines of the mercury spec agreement with that deduced theoretically from trum. A. C a r r e l l i (Atti R. Aecad. Lincei, 1928, Schrodinger’s theory (5-37). The ratio of the absorp [vi], 7, 1014— 1018).—A discussion of the results of tion maxima in the two lines also agrees with that the measurement, by the interferometer method, of calculated from the theory. J. W. S m i t h . the breadth of eleven lines of the mercury spectrum. F. G. T r y h o r n . Promotion of the emission of the Balmer Spectra of ionised neon (Ne n) and ionised lines b y the addition of argon. E. H ie d e m a n n argon (A II). II. T. L. d e B r u i n (Proc. K . (Z. Physik, 1928, 50, 609—617).—It has been shown Akad. Wetensch. Amsterdam, 1928, 31, 593—602). that the addition of argon produces a very marked —A comparison is made between the quadruplet effect on the relative intensities of the lines and terms of ionised neon (Ne ii) and ionised argon (A ii). bands in the hydrogen spectrum. The action of A table of terms is given. Nearly all the terms pre argon on the dissociation of the hydrogen molecule dicted by the theory of Heisenberg and Hund have into ions and on the recombination of the latter is been detected and identified. The Zeeman effect was discussed. A theory is developed which is claimed investigated in order to check the term scheme, the to agree with the observed phenomena. calculated effect being compared .with that observed. J . W. S m it h . A. J. M e e . Fulcher spectrum of hydrogen. E. H i e d e Intensity of reflexion of X-rays by crystals m a n n (Z. Physik, 1928, 50, 618—625).—From a dis and the Compton effect. G. E. M. J a u n c e y cussion of the existing data the conclusion is reached (Physical Rev., 1927, [ii], 29, 206).—A correction that the Fulcher bands in the hydrogen spectrum are factor, introduced-by the Compton effect, is applied 4 o 1293 1294 BRITISH CHEMICAL ABSTRACTS.— A. to Bragg, Darwin, and James’ formula (A., 1926, 663) Excitation of the arc spectrum of nitrogen. for the case of an ideally imperfect crystal. R. A. W o l f e and 0. S. D u f f e n d a c k (Physical Rev., A. A. E l d r i d g e . 1927, [ii], 29, 209—210).—When the arc spectrum of X-Ray spectrographic measurements in the nitrogen was excited by an interrupted low-voltage L and M series of rhenium. H. B e u t h e (Z. arc in a mixture of helium and nitrogen, nitrogen arc Physik, 1928, 50, 762—768).—The wave-lengths of a lines were very strong in a limited region, whereas in number of La, [3, and y and of fl/p and y lines of other regions helium lines or nitrogen bands strongly rhenium have been determined, and the correspond predominated. Existing data are largely confirmed. ing term values have been calculated. A. A. E l d r i d g e . R. W. L u n t . Absorption spectrum of antimony vapour. Intensities of If-series X-rays from thin R. V. Z u m s t e in (Physical Rev., 1927, [ii], 29, 209). targets. D . L. W e b s t e r , H. C l a r k , R. M. Y e a t - —The arc lines 2311-50, 2175-88, and 2068-38 were m a n , and W. W. H a n s e n (Proc. Nat. Acad. Sci., strongly, and 2023-86, 2127-46 less strongly, absorbed. 1928, 14, 679—686).—Experimental data have been All five absorption lines come from the 3d2 state, obtained for targets of silver so thin as to cause no which is doubtless the normal state of the atom. appreciable retardation of most of the cathode rays. A. A. E l d r i d g e . These data give the relative intensity of X-series Resonance glow in a hydrogen discharge tube. X-rays, and, therefore, the relative probability of R. D . R u s k (Physical Rev., 1927, [ii], 29, 213—214). direct X-electron ionisation, as a function of cathode- —A study of the blue haze obtained in a hot-filament ray energy from the excitation energy to 3-3 times that discharge tube. A close relationship between the life amount. W. E. D o w n e y . of the excited molecule and its collision frequency is suggested. A. A. E l d r i d g e . Relation between chemical constitution and X-absorption spectra. VII. General review. Absorption of the mercury line 1941-5 A. in 0. S t e l l i n g (Z. Physik, 1928, 50, 506—530).—Fol the positive column and the optical determin lowing a review of the various experimental methods ation of the concentration of mercury ions. now employed, the author analyses the results W. d e G r o o t (Z. Physik, 1928, 50, 559—569). obtained with the compounds of phosphorus, sulphur, —Radiation of 1941-5 A. emitted from a low-voltage and chlorine. In the phosphorus compounds it is arc in a neon-mercury vapour mixture was allowed to shown that the displacement of the absorption limit pass through the positive column of a low-voltage depends only on the nature of the atom or radical discharge in a mixture of argon (16 mm.) and mercury directly linked to the phosphorus, and that the displace vapour (3 mm.); the ratio of the intensity of the ment is proportional to the number of such atoms or incident to the transmitted radiation, I 0/I, has been radicals. The limit for sulphur shifts towards shorter measured as a function of the current in the positive wave-lengths as the valency is increased ; the influence column. A theoretical expression for this ratio has of metals in sulphides is specific to the metal, but the been derived from the analyses of Lorentz, Voigt, position of the limit is constant in organic compounds and Minkowski in terms of the most probable velocities, of sulphur.

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