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sition of the gas evolved during the reaction is satisfactorily explained on this basis. The work is being continued.

R. p. m. as catalyst: C. H, MILLIGAN and E. EMMET REID. It has long been known that ethylene can be used in place of ethyl chloride in the preparation of ethyl benzene by the Friedel and Crafts reaction but the absorption rate is so slow under usual conditions that the method has not been attractive for preparing ethyl benzene. We find that the reaction can be made to go 80 rapidly by using a high speed stirrer that this becomes an efficient preparation method. A mixture of 250 g. benzene and 50 g. aluminum chloride absorbs as much as 1,800 c.c. of ethylene per minute when stirrer is run at 1,300 r. p. m.

Catalysis in the interaction of carbon with steam and carbon dioxide: H. A. NEVILLE and H. S. TAYLOR. The catalytic activity of alkali carbonates, alkaline earths and various salts in promoting reaction between steam and carbon has been shown to be paralleled by similar effects in the acceleration of interaction of carbon and carbon dioxide. In each case potassium carbonate has been found to be the most active salt catalyst. Reduced nickel promotes interaction of carbon and carbon dioxide markedly. In explanation of the mechanism of the two reaction processes it has been shown that adsorption of carbon dioxide by carbon at 445° C. is markedly increased by addi. tion to the carbon of such accelerating agents, although these latter themselves show no adsorptive capacity for the gas.

Catalysis in the reduction of oxides and the catalytic combination of hydrogen and oxygen: R. N. PEASE and H. S. TAYLOR. Oxygen and water vapor, present in hydrogen used for reduction of copper oxide, markedly inhibit the action; addition of reduced copper to the oxide appears to accelerate the reaction. The induction period in the reaction is attributed (a) to initial drying of the oxide, (b) to slow initial formation of copper which then acts as a catalyst. It is doubtful whether the catalytic combustion of hydrogen and oxygen in presence of copper can be represented as an alternate oxidation and reduction process as it has been found that when hydrogen containing oxygen is passed over copper oxide at 150° C., no appreciable water is formed and, at lower temperatures, the activity is reduced as the catalyst becomes progressively oxidized. The formation of water in presence of copper may take place through interaction of hydrogen on an oxygen molecule which is in process of combining to

form oxide, that is, at the instant of collision with the copper surface.

A case of autooxidation : Mn0, → AMnO,: J. C. FRASER,

Oxidation and reduction by organic compounds: C. H. MILLIGAN and E. EMMET REID.

The action of alumina, titania, and thoria on ethyl and isopropyl acetate: HOMER ADKINS and A. C, KRAUSE.

The catalytic electrolytic oxidation of 30,: COLIN G. FINK. The electrolytic oxidation of So, with various anodes was investigated. It was found that graphite anodes will catalyze the oxidation providing ferrous-ferric ions are present in solution. In the absence of iron, no catalytic effect due to the graphite could be observed. On the other hand, an inert anode such as ferrosilicon, in the presence of ferrous-ferric ions will not catalyze the son oxidation. The combined effect of the graphite anode and the iron is .essential to accelerate the reaction.

The decomposition of ethyl acetate induced by catalytic nickel: HOMER ADKINS and P. W. SIMMONDS.

The catalytic influence of foreign oxides on the decomposition of silver oxide, mercuric oride and barium peroxide: JAMES KENDALL and FRANCIS J. FUCHE. The effect of foreign oxides on the temperature and rate of decomposition of silver oxide, mercuric oxide and barium peroxide under an oxygen pressure of one atmosphere has been experimentally investigated. In almost all of the systems examined, the added oxide induces a considerable change in the decomposition temperature. Most commonly there is a marked lowering in this point; thus (to cite an extreme case) an equimolecular mixture of Bao, and CuO has an oxygen equilibrium pressure of one atmosphere at 355°, approximately 500° below the decomposition temperature of pure BaOz. In a few systems a comparatively small rise in the decomposition temperature is indicated. In all instances, however, the rate of oxygen evolution is significantly inereased.

A new clock reaction: G. S. FORBES, H. W. ESTILL, and 0. J. WALKER. The induction period, t, preceding precipitation of Ass, from HAsO, or H AsO, in the presence of H.,8,02, is extraordinarily sharp and reproducible. In the case of H,AsOz, 1/t=KC Na S,O3, but is independent of C H,AsOs, and also of C H provided HC,H,O, or very dilute HCl is used. The period increases greatly with C HC. The rate of precipitation, also highly reproducible, is very great at first, diminishes vory rapidly, but may not become zero before 3,000 hours at room temperature. With HC,H,O, the initial rate=k'C H, but with moderate values of C HCl this proportion becomes inverse. Many other regularities, likewise afford. ing clues to the reaction mechanism, have been noted. A quantitative study of adsorption in solution and at interfaces of sugars, dextrin, starch, gum arabic and egg albumen, and the mechanism of their action as emulsifying agents: GEORGE L. CLARK and Wm. A, Mann. By the most accurate method known—the use of the stalagmometer for measurement of interfacial tension and the Morgan drop weight apparatus for measurement of surface tension of single liquids—the adsorption of sugar in solution has been determined to be negative, the adsorption increasing in ratio with increase in concentration of sugar, while the adsorption of sugar at the interface is positive and increases in the same ratio as in solution. Dextrin and starch, in very dilute solutions, are negatively adsorbed in solution but, in more concentrated solutions, are positively adsorbed while at the interface they are negatively adsorbed-starch more so than dextrin. Gum arabic behaves, in this respect, in the same manner as starch. A favorable surface tension, seemingly, is not a prerequisite for a good emulsion with any solution studied, although viscosity is an important factor. Better emulsions have been obtained with egg albumensaturated solutions—than with any other solution under inspection,

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The volumetric oxidation of sulfide to sulfate: H. H. WILLARD and W. E. CAKE. The alkaline sul. fide solution obtained by absorbing H,8 in NaOH is oxidized quantitatively to sulfate if excess of standard hypobromite or hypochlorite is added, and sufficient hydroxide is present. The excess is then determined by adding KI, acidifying, then titrating the iodine with thiosulfate. The method may be applied also to freshly precipitated sulfides, such as Zns. Since four times as much oxygen is required in this reaction as in the usual iodine titration, the method is especially suitable for small amounts of sulfur.

Making scientists: Recovering the normal ouri. osity in college students: EDWARD ELLERY. A normal boy and the investigating scientist have this in common—they are both living interrogation points. The investigator minus a “why” is an anomaly, and a boy without it is abnormal, if not defective. If college training knocks the natural "why” out of a boy, a reform can not too soon be instituted. Here is the way Union College is working to effect such a reform. At every opportunity work is required that takes the boy away from his textbook and laboratory manual and into the library for consultation of larger treatises and current periodicals. In the summer months, at the end of the junior year, a few of the best stu. dents receive appointments to the research laboratory of the General Electric Company, where they handle a piece of research work under the direct supervision of the leading members of the staff of that organization. In their last year in col. lege, their time in the chemical laboratory is given to a continuation of this research work, or to a new problem. It is only the unconquerably dull boy that fails to react to this effort to awaken his natural “why."

The apparent irreversibility of the calomel electrode: A. W. LAUBENGAYER. When mercury is made anode in a chloride solution a high-resistance, black film forms over the surface of the mercury. This is composed of drops of mercury and particles of mercurous chloride. It is not known why mercurous chloride should be adsorbed so closely and mercurous sulphate not.

The theory of hydrogen overvoltage: D. A. MACINNES and W. R. HAINSWORTH. Experiments on the effect of pressure on hydrogen overvoltage show that the variation produced is in the direction predicted by the theory advanced by MacInnes and Alden; i.e., the overvoltage increases when the pressure is decreased. On the other hand, computation of the overvoltage from the size of evolved bubbles fails for layer potentials, since the phenomena at metal suịfaces get farther and farther away from equilibrium conditions as higher overvoltages are reached. However, the fundamental assumption that overvoltage is an extreme case of concentration polarization, retains its usefulness in explaining the experimental results, at least for the lower potentials.

The hydrogen electrode under high pressures : W. R. HAINSWORTH. The variation of the E. M. F. of the cell, H,1HC1 (C.1nHCI), HgCl/Hg, with pressure has been measured from one to 400 atmospheres. It was found that thermodynamic cal. culations involving (1) the deviation of hydrogen from a perfect gas, (2) the partial molal volume of HCl in 0.1 NHCI, (3) the molal volumes of mercury and calomel, and (4) the change of HCI concentration with the compressibility of the solution, served to reproduce the observed potential of the cell within 0.2 mv. throughout the pressure range studied. This leads to the conclusions, (a) that the thermodynamic environment” is not appreciably changed by the molecular hydrogen in solution, or by compression, and (b) that the fugacity (or effective pressure) of hydrogen can be calculated up to 400 atmospheres from the equation of state developed by Keyes.

Potassium ammonoaluminate and ammonomanganite: FRANCIS W. BERGSTROM. The author has added an ammonoaluminate and an ammonomanganite of potassium to Franklin's list of salts formed by the action of potassium amide, in liquid ammonia solution, on the amides, imides or nitrides of other metals. The aluminate has been prepared by the action of a solution of potassium amide on amalgamated metallic aluminium. Its composition is represented by the formula Al(NHK) (NH,)Potassium ammonomanganite has been obtained in the form of rose colored crystals by the action of an excess of potassium amide on manganese thiocyanate in accordance with the reaction represented by the equation

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The preparation, properties and molecular volume relationships of the ammines and hydrates of cobaltous fluoride, bromide, nitrate, carbonate and citrate: GEORGE L. CLARK and H. K. BUCKNER.

The molecular volume compression of the subsidiary valence groups, NH, and H.0, were studied in the same manner as in the previous work on the chloride and sulphate of cobalt (J. Am. Chem. Soc., 42, 2483 (1920)) in light of difference in volumes between anion and cation and possibilities of space cavities. It was confirmed that the larger the difference between anion and cation the greater the possibility of cavities, and the less the compression of NH, and 1,0 required the more stable the compound and the greater the possibility of holding a maximum number of groups. The various compounds prepared and studied are distinctly new with the exception of cobaltous bromide hex. ammine and cobaltous nitrate hexammine, the following being representative: cobaltous fluoride hexammine, cobaltous nitrate di-hydrate, ammines of cobaltous nitrate indicating more than six subsidiary valence groups and ammines of cobaltous carbonate and citrate.

Emulsification with soaps of linoleic and rici. noleic acids : GEORGE L. CLARK and H. K. BUCK

NER. This work has involved the quantitative study by means of surface energy measurements for solutions and at the interface between aqueous solution and a pure oil by the drop weight method of the following points: the solubility in water of the free acids from the log. concentration-surface tension curve; the adsorption at the surface and the volume occupied by each molecule in the surface; the surface tensions of various concentrations of the soaps in solution, the effect upon the interfacial tension between water and pure toluene, the effect of the hydrolysis of the soap and the prevention of hydrolysis by the addition of various concentrations of NaOH to a given concentration of the soap; a test of the antagonistic effect of sodium and calcium soaps by testing the effect upon the interfacial tension between water and toluene containing a small amount of the free acid of adding various salts of sodium and calcium, resulting in the fact that the sodium salt promotes emulsions of oil in water and calcium salts promote emulsions of water in oil; and finally a thorough comparison of all the data so obtained with previous work on soaps of palmitic, stearic and oleic acids. All results of this purely quantitative study, are necessarily numerical and can not be included in a short abstract.

Notes on the preparation of pure platinum: EDWARD WICHERS. The paper briefly states the method used in preparing platinum sponge free from other platinum metals and base metals, and describes in more detail the work that has thus far been done on the conversion of this sponge to compact metal with minimum contamination. E.M.F. tests show the resulting platinum to bo of higher purity than the best previously obtainable, i.e., the thermoelement wire of Heraeus, and show the difference in purity to be a matter of calcium content. Results of experiments with magnesia refractories are also given. There is a brief outline of further work to be done on this subject.

Modified method for the determination of iron and vanadium after reduction by hydrogen sulphide: G. E. F. LUNDELL and H. B. KNOWLES. Published methods for the determination of iron and vanadium after reduction by hydrogen sul. phide ordinarily yield high values. A modified method which is sufficiently accurate for most purposes is presented, and a procedure for accurate analysis is outlined.

The free energy of dilution of hydrobromic acid; the activities of its ions in very dilute and con

centrated solutions : MILLER SPENCER and ALBERT YOUTZ. The authors, in searching for definite G. LOOMIS.

evidence of depolarization in the electrolytic haloThe ultra-violet arc spectrum of yttrium: L. F.

genation of organic compounds, found that either YNTEMA and B. S. HOPKINS. The ultra-violet arc

slow reaction rate or slow diffusion, or both, prespectrum of Y was measured, using the yttrium

vented any marked depolarization. Experiments oxide prepared by one of us for the determination

on the oxidation of FeCl, in HCl gave surprisingly of the atomic weight value accepted by the Inter

accurate information as to the rate of diffusion national Committee. The spectrograph used is an

under a variety of conditions, and showed that autocollimating quartz prism machine manufac

without stirring there is a film of stationary liquid tured by Adam Hilger, of London. A current of

about 0.5 mm. thick through which diffusion must 4 amperes at an E.M.F. of 220 volts was passed

take place. This emphasizes the great importance between vertical copper electrodes, the lower of

of violent stirring and of the use of rapidly difwhich held the Y,0, in its crater. Several promi.

fusing inorganic carriers to extend the sphere of nent lines, attributed to Y in the literature, were

the organic reaction from a surface to a volume. absent, and several new lines were measured. The Observations on the drying and swelling of gelaresults given are the mean of five determinations. tine gels: S. E. SHEPPARD and F. A. ELLIOTT. At

tention is drawn to the importance of capillarity On the viscosity of gelatin sols: ROBERT HERMAN BOGUE. Experiments were carried out upon

in the first phase of drying of jellies. It is shown gelatin sols to accurately determine the relation

that this, in conjunction with factors depending between viscosity and concentration. The data

upon the shape of the jelly, causes the formation

of an exo-skeleton tending to conserve or increase have been applied to Hatschek's formula for the

the original external surface extension. It is viscosity of emulsoids and the value A/A, representing the volume occupied per unit weight of

chiefly due to this, rather than to any internal dispersed phase, was shown not to be constant

supermolecular structure, that dried jellies on re

swelling in water tend to return to their original with varying concentration, but to rise to a maxi

concentration, mum and thereafter regularly decline. A tentative explanation is presented based upon the effect Note on the influence of silver salts in catalyzwhich increasing concentrations of dispersed phase

ing the decomposition of ammonium persulphate will have upon the surface tension of the disper

solutions: S. E. SHEPPARD and A, BALLARD. The sion medium. An empirical expression defining influence of silver salts in facilitating the decomthe departure of the values obtained under varying position of ammonium persulphate in solution, first conditions for Hatschek's constant is given. observed by H. Marshall and J. Inglis, has been

confirmed, and quantitative data on the rate of The structure of molecules of water: IRVING

change in relation to the silver content obtained. LANGMUIR. Dennison has recently shown by X

Further developments of the hydrogen elecray crystal analysis that ice consists of molecules

trode: FELIX A. ELLIOTT. Two new forms of hyof the formula H.Oz. In view of our knowledge

drogen electrode were described representing probof the structure of atoms it is not possible to ac

ably the limits of simplicity and ruggedness withcount for the existence of this molecule on the

out reducing accuracy and rapidity of operation. basis of quadrivalent oxygen atoms. If pairs of

Especial attention has been given in designing electrons (duplets) constitute the valence bond, there can be no such bon betwee

the two oxygen

this new apparatus to reduce the internal resis

tance to the lowest possible value so that a less atoms. A structure for this molecule is therefore

sensitive and hence cheaper, simpler and portable proposed in which the four hydrogen nuclei bind

electrical measuring instrument might be used. the two oxygen atoms. The duplet held by each

Such an instrument was described, working on the hydrogen nucleus has one of its electrons in each

potentiometer principle and employing a pivot type of the oxygen octets, instead of the more usual ar

movement. Examples of results obtained with the rangement in which both electrons of a duplet

two types of apparatus indicate that potentials form part of the same octet.

are reproducible to about 0.1 mv. The purification of helium by means of charcoal:

Note on silver soap gels: G. STAFFORD WHITBY. L. FINKELSTEIN.

It has been observed that the silver salts of the The importance of diffusion in organic electro- fatty acids are capable of giving reversible gels chemistry: ROBERT E. WILSON and MERRILL A. in a variety of organic liquids-particularly in the

homologs of benzene and in halogenated derivatives of benzene and its homologs. The silver salts form gels at a lower point in the series of saturated fatty acids than do the alkali-metal salts; gels being obtained with silver caproate. A number of regularities were discernible. The silver salts of the higher members of the saturated fatty acid series show a greater solvation capacity than those of the lower ones. None of the saturated fatty acid silver salts gave a gel in benzene; but silver oleate did. Speaking generally, in the case of solvents of the same general chemical character, the higher the boiling point of the solvent, the greater appeared to be the solvation capacity of a given salt, and the smaller the extent to which the gel from a given salt suffered syneresis.

Catalytic effect in the reaction between ketones and halogens in aqueous solutions: F. O. RICE. The velocity constant of the reaction between acetone and bromine is independent of the bromine concentration and Lapworth (J. C. S. Trans., 1904, p. 30) explained this by saying that the acetone slowly enolized and the addition of bromine and splitting off of hydrobromic acid were practically instantaneous. This is probably incorrect since higher ketones have the same velocity constant as acetone, and an explanation based on the radiation theory was offered. The reaction is accelerated by neutral salts contrary to Lapworth's statement.

The transference numbers of sulfuric acid by the concentration cell method: A. L. FERGUSON and W. G. FRANCE. A cell combination was used which permitted the measurement of all the required potentials from one set-up. The value obtained for the transference number for the anion in concentrations between M/10 and M/100 at 25° C. was ,1868 +.0007. The method was shown to be highly reliable. In all of the calculations it was assumed that sulfuric acid dissociates into two hydrogen and one sulfate ion. This assumption was substantiated by the results obtained. A formula for boundary potential was developed in which boundary potential may be obtained from potential measurements alone.

The influence of gelatin on the transference numbers of sulfuric acid: ALFRED L. FERGUSON and W. G. FRANCE. The transference numbers were determined by the concentration cell method. So. lutions of sulfuric acid containing from 0.5 per cent. to 20 per cent. gelatin were used. The transference numbers of the anion increased from .187 for pure acid to .685 for acid containing 20 per

cent. gelatin. In the 20 per cent. gelatin solution the boundary potential of both concentration cells became zero. The decrease in conductivity was approximately proportional to the gelatin added. The results are probably best explained on the assumption that there is a chemical action between the gelatin and sulfuric acid in which a single compound is formed. In this compound the hydrogen of the acid loses its identity and when the compound dissociates there is formed a complex gelatin hydrogen positive ion and a negative sulfate ion.

The entropy of monatomic gases: GILBERT N. LEWIS.

The electrometric titration of uranium with potassium dichromate and potassium permanganate: D. T. EWING and E, F, ELDRIDGE.

The heat of coagulation of ferric oxide hydrosol by electrolytes: FREDERICK L, BROWN and J. H. MATHEWS.

Some quantitative experiments on coagulation of colloids: RAY V. MURPHY and J. H. MATHEWS. The lowest concentration (limiting concentration) of electrolytes necessary to coagulate hydrous ferric oxide sol has been studied as a function of the purity of the sol (ratio of gram-equivalents of Fe to gram-equivalents of CI) and of the concentration of Fe.Oz. Chloride, chromate and ferricyanide ions were used in the form of the potassium salts. The conclusions drawn are: (1) The limiting concentration decreases with increasing purity in the case of all three ions, the mechanism of the process being evidently similar for the three ions; (2) The limiting concentration decreases markedly with decreasing concentration of the sol in the case of all three ions, but the relation indicated by Burton and Bishop, Jour. Phys. Chem., 24, 701 (1920), for mastic, As.Sa and Cu sols, holds for Fe,Og hydrosol only in the case of the trivalent ion.

The alkalinity of Searles Lake brine: ROGER C. WELLS. The title may mean either the titration alkalinity or the hydrogen ion concentrations. The latter may be considered as determined by certain proportions of the four buffer substances Na,CO2, NaHCO3, Na,B,0,, and Na,B,0. The writer has found for the brine Pu=9.48. By determining the Ph values of artificial brines containing each pair of buffers separately it is possible to draw curves from which by interpolation the proper proportions of the buffers to yield PH 9.48 may be read. This method serves as a check of the analyti

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