Neutral Salt Solutions Research Articles

The Activity Coefficient of Benzoic Acid in Solutions of Neutral Salts and of Sodium Benzoate

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Activity Coefficient of Benzoic Acid in Solutions of Neutral Salts and of Sodium BenzoateI. M. KolthoffI. M. KolthoffMore by I. M. Kolthoff and Wouter BoschWouter BoschMore by Wouter BoschCite this: J. Phys. Chem. 1932, 36, 6, 1685–1694Publication Date (Print):June 1, 1932Publication History Published online1 May 2002Published inissue 1 June 1932https://doi.org/10.1021/j150336a005RIGHTS & PERMISSIONSArticle Views214Altmetric-Citations19LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (464 KB) Get e-Alerts

Interaction between Copper Oxide and Neutral Salt Solutions

Interaction between Copper Oxide and Neutral Salt Solutions

Hydrolysis of esters in weak acid.—Neutral salt solutions

The flow and electrical birefringence in solution of a number of fractions of para-aromatic polyester are studied, using dioxane and dichloracetic acid as solvents. In passing from a non-polar (dioxane) solvent to a polar solvent the optical and hydrodynamic properties of the molecular chain remain unchanged, whereas the electro-optical characteristics undergo sharp changes. The hydrodynamic and dynamo-optical characteristics of the polymer under study in dioxane correspond to the properties of a typical rigid chain polymer, whereas the electro-optical properties are typical of a flexible chain. This unique combination of properties can be explained by the specific dipole structure of the monomer unit and the significant difference in the longitudinal and lateral dipole rigidity of the polymer chain of the polyester under study.

THE ACTIVITY OF PHENOL IN AQUEOUS SALT SOLUTIONS

Abstract 1. From the measurements on the partition of phenol between benzene and the aqueous solutions of neutral salts, it has been found that the following logarithmic law practically holds, (Remark: Graphics omitted.) Applying this to the equation of the chemical potential of phenol it becomes (Remark: Graphics omitted.) We have also obtained an equation of phenol distribution between benzene and water in the presence of neutral salts at 25°C: B=2.272×10βSC+37.71×103βSC3. 2. From the measurements of the freezing points of the aqueous phenol solutions in the presence of a neutral salt, it has qualitatively been proved that the chemical potential of phenol can be expressed in the following formula, X=Z0+αS+RTlnC and the activity coefficient of phenol is, therefore, to be expressed as (Remark: Graphics omitted.)

CCXLI.—Chemical action at an interface: the production of acidity in neutral salt solutions

CCXLI.—Chemical action at an interface: the production of acidity in neutral salt solutions

RESEARCH ON THE ELECTROLYTIC REDUCTION POTENTIALS OF ORGANIC COMPOUNDS

(1) The reduction potential of nicotinic acid was measured with the dropping mercury cathode and the polarograph. (2) Two stages of the reduction process were observed. (3) For the first stage of reduction, observed R-P. was compared with the theoretical value calculated by the following formula at 15°C., π=-0.05713/2logk'/?H.?2CC5H4N•COOH in which by taking the R. P. of 0.01 mol nicotinic acid in (0.01n HCl+0.1n KCl) solution, i.e. -0.984V as a standard, we have log k=28.33 In an acidic as well as in a neutral salt solution, the observed R. P. showed satisfactory concordance with the calculated values, and thus the first stage has been concluded to be the reduction of the carbonyl group of nicotinic acid to aldehyde. (4) The second stage of reduction is considered to be the reduction of pyridine ring of nicotinic acid, by comparison with the R. P. of pyridine in our preceding paper. (5) The reduction of nicotinic acid in an excess of alkali, does not take place, owing, perhaps, to the desorption of negatively charged nicotinic acid ions to the polarised mercury cathode. R. P. in a sodium acetate or sodium bicarbonate solution was about 0.02V more negative than the calculated value. (6) Maximum of current voltage curve was observed in sodium bicar-bonate solution, in which the potential of maximum current intensity was almost independent of the concentration of nicotinic acid. (7) The reduction potential of benzoic acid was studied for the sake of comparison, with the result that in hydrochloric acid, no reduction but only the deposition of hydrogen ion has been seen, while a potassium chloride solution the R. P. is over 0.240V negative than that of nicotinic acid. Thus the group effect of a carbonyl group is considered to be more effective than a benzene ring. (8) The decisive conclusion as to the reduction process has been left out for the time, when the isolation of the reduction product, now under investigation, would be completed.

THE PENETRATION OF BASIC DYE INTO NITELLA AND VALONIA IN THE PRESENCE OF CERTAIN ACIDS, BUFFER MIXTURES, AND SALTS

When living cells of Nitella are exposed to an acetate buffer solution until the pH value of the sap is decreased and subsequently placed in a solution of brilliant cresyl blue, the rate of penetration of dye into the vacuole is found to decrease in the majority of cases, and increase in other cases, as compared with the control cells which are transferred to the dye solution directly from tap water. This decrease in the rate is not due to the lowering of the pH value of the solution just outside the cell wall, as a result of diffusion of acetic acid from the cell when cells are removed from the buffer solution and placed in the dye solution, because the relative amount of decrease (as compared with the control) is the same whether the external solution is stirred or not. Such a decrease in the rate may be brought about without a change in the pH value of the sap if the cells are placed in the dye solution after exposure to a phosphate buffer solution in which the pH value of the sap remains normal. The rate of penetration of dye is then found to decrease. The extent of this decrease is the greater the lower the pH value of the solution. It is found that hydrochloric acid and boric acid have no effect while phosphoric acid has an inhibiting effect at pH 4.8 on stirring. Experiments with neutral salt solutions indicate that a direct effect on the cell (decreasing penetration) is due to monovalent base cations, while there is no such effect directly on the dye. It is assumed that the effect of the phosphate and acetate buffer solutions on the cell, decreasing the rate of penetration, is due (1) to the penetration of these acids into the protoplasm as undissociated molecules, which dissociate upon entrance and lower the pH value of the protoplasm or to their action on the surface of the protoplasm, (2) to the effect of base cations on the protoplasm (either at the surface or in the interior), and (3) possibly to the effect of certain anions. In this case the action of the buffer solution is not due to its hydrogen ions. In the case of living cells of Valonia under the same experimental conditions as Nitella it is found that the rate of penetration of dye decreases when the pH value of the sap increases in presence of NH(3), and also when the pH value of the sap is decreased in the presence of acetic acid. Such a decrease may be brought about even when the cells are previously exposed to sea water containing HCl, in which the pH value of the sap remains normal.

Certain Physico-Chemical Characteristics of Muscle Globulin.

The significance of the protein constituents of muscle for the contractile process has long been recognized. The instability of these bodies, however, has rendered difficult their characterization. Danilewsky described the extraction of muscle protein with sal ammoniac in 1881. The older method of expression, despite rigid precautions, often led to “denaturation” or “clotting of muscle plasma.” The properties of muscle globulin, as of other globulins, are altered both by too low salinity and by too high acidity. Howe has employed phosphate buffers as solvents to overcome these difficulties. In the present investigation an ammonium chloride solution, rendered alkaline by excess of ammonia, was used as solvent and yielded solutions of muscle protein which, for several months, retained solubility in neutral salt solutions. A globulin-like fraction of ox muscle protein was studied, which presumably corresponded to the “myosin” of von Fürth and the “paramyosinogen” of Halliburton. The method of preparation depended upon: (a) its low solubility in water or dilute salt solution; (b) its greater solubility in the presence of higher concentrations of neutral salt; (c) its precipitation from solutions less than half-saturated with respect to ammonium sulfate. Fresh muscle was finely ground and stirred into a two-molal ammonium chloride solution, to which ammonium hydroxide was slowly added to a concentration one-third normal. This ammonia buffered the acid products and thus prevented “denaturation.” The dissolved protein, after centrifugation and filtration, was alternately precipitated by ammonium sulfate, dissolved in more dilute salt solution, and precipitated by further dilution. The reaction was always maintained between pH 8.0 and 8.5 by ammonia. Precipitated by ammonium sulfate, the muscle globulin was freed from albumins and hemoglobin; precipitated by dilution from the serum globulins which dissolve in more dilute salt solutions.

The Action of Certain Reagents on Amoeboid Movement

The Action of Certain Reagents on Amoeboid Movement

The Action of Solutions of Neutral Salts on Soil. A Contribution to the Knowledge of Soil Acidity

The Action of Solutions of Neutral Salts on Soil. A Contribution to the Knowledge of Soil Acidity

The Influence of Some Neutral Salt Solutions, Intravenously Administered, on the Reserve Alkali of the Blood

The Influence of Some Neutral Salt Solutions, Intravenously Administered, on the Reserve Alkali of the Blood

Permeability of the Cell to Electrolytes

The effects of a salt upon the permeability of Laminaria may be predicted according to the following rule. Neutral salt solutions of the same osmotic pressure and conductivity as sea water cause an initial decrease in permeability, followed by an increase if the valency of the cation is greater than that of the anion. They cause an increase in the permeability from the start if the valency of the cation is less than that of the anion. If the two are of the same valency the effect will depend upon the relative size of the ions and the density of the accompanying electric charges. A hypothesis is proposed to explain the observed phenomena which may be summarized as follows: (1) Permeability is due to the electrical condition of the semipermeable membrane, which in Laminaria is negatively charged when in sea water. (2) A solution in which the cation carries the more dense charge, a positive salt, alters the charge on the membrane and decreases the permeability. As more of the salt diffuses in, the negative...

CCXLIV.—Reactions of cellulose with sodium chloride and other neutral salt solutions. Part I. Preliminary survey

CCXLIV.—Reactions of cellulose with sodium chloride and other neutral salt solutions. Part I. Preliminary survey

THE ORIGIN OF THE POTENTIAL DIFFERENCES RESPONSIBLE FOR ANOMALOUS OSMOSIS

1. Collodion bags coated with gelatin on the inside were filled with a M/256 solution of neutral salt (e.g., NaCl, CaCl(2), CeCl(3), or Na(2)SO(4)) made up in various concentrations of HNO(3) (varying from N/50,000 to N/100). Each collodion bag was put into an HNO(3) solution of the same concentration as that inside the bag but containing no salt. In this case water diffuses from the outside solution (containing no salt) into the inside solution (containing the salt) with a relative initial velocity which can be expressed by the following rules: (a) Water diffuses into the salt solution as if the particles of water were negatively charged and as if they were attracted by the cation and repelled by the anion of the salt with a force increasing with the valency of the ion. (b) The initial rate of the diffusion of water is a minimum at the hydrogen ion concentration of about N/50,000 HCl (pH 4.7, which is the point at which gelatin is not ionized), rises with increasing hydrogen ion concentration until it reaches a maximum and then diminishes again with a further rise in the initial hydrogen ion concentration. 2. The potential differences between the salt solution and the outside solution (originally free from salt) were measured after the diffusion had been going on for 1 hour; and when these values were plotted as ordinates over the original pH as abscissae, the curves obtained were found to be similar to the osmotic rate curves. This confirms the view expressed by Girard) Bernstein, Bartell, and Freundlich that these cases of anomalous osmosis are in reality cases of electrical endosmose where the driving force is a P.D. between the opposite sides of the membrane. 3. The question arose as to the origin of these P. D. and it was found that the P.D. has apparently a double origin. Certain features of the P.D. curve, such as the rise and fall with varying pH, seem to be the consequence of a Donnan equilibrium which leads to some of the free HNO(3) being forced from the solution containing salt into the outside solution containing no (or less) salt. This difference of the concentration of HNO(3), on the opposite sides of the membrane leads to a P.D. which in conformity with Nernst's theory of concentration cells should be equal to 58 x (pH inside minus pH outside) millivolts at 18 degrees C. The curves of the values of (pH inside minus pH outside) when plotted as ordinates over the original pH as abscissae lead to curves resembling those for the P. D. in regard to location of minimum and maximum. 4. A second source of the P.D. seems to be diffusion potentials, which exist even if no membranes are present and which seem to be responsible for the fact that the rate of diffusion of negatively charged water into the salt solution increases with the valency of the cation and diminishes with the valency of the anion of the salt. 5. The experiments suggest the possibility that the establishment of a Donnan equilibrium between membrane and solution is one of the factors determining the Helmholtzian electrical double layer, at least in the conditions of our experiments.

THE INFLUENCE OF ELECTROLYTES ON THE ELECTRIFICATION AND THE RATE OF DIFFUSION OF WATER THROUGH COLLODION MEMBRANES

1. When pure water is separated by a collodion membrane from a watery solution of an electrolyte the rate of diffusion of water is influenced not only by the forces of gas pressure but also by electrical forces. 2. Water is in this case attracted by the solute as if the molecules of water were charged electrically, the sign of the charge of the water particles as well as the strength of the attractive force finding expression in the following two rules, (a) Solutions of neutral salts possessing a univalent or bivalent cation influence the rate of diffusion of water through a collodion membrane, as if the water particles were charged positively and were attracted by the anion and repelled by the cation of the electrolyte; the attractive and repulsive action increasing with the number of charges of the ion and diminishing inversely with a quantity which we will designate arbitrarily as the "radius" of the ion. The same rule applies to solutions of alkalies. (b) Solutions of neutral or acid salts possessing a trivalent or tetravalent cation influence the rate of diffusion of water through a collodion membrane as if the particles of water were charged negatively and were attracted by the cation and repelled by the anion of the electrolyte. Solutions of acids obey the same rule, the high electrostatic effect of the hydrogen ion being probably due to its small "ionic radius." 3. The correctness of the assumption made in these rules concerning the sign of the charge of the water particles is proved by experiments on electrical osmose. 4. A method is given by which the strength of the attractive electric force of electrolytes on the molecules of water can be roughly estimated and the results of these measurements are in agreement with the two rules. 5. The electric attraction of water caused by the electrolyte increases with an increase in the concentration of the electrolyte, but at low concentrations more rapidly than at high concentrations. A tentative explanation for this phenomenon is offered. 6. The rate of diffusion of an electrolyte from a solution to pure solvent through a collodion membrane seems to obey largely the kinetic theory inasmuch as the number of molecules of solute diffusing through the unit of area of the membrane in unit time is (as long as the concentration is not too low) approximately proportional to the concentration of the electrolyte and is the same for the same concentrations of LiCl, NaCl, MgCl(2), and CaCl(2).

STUDIES ON THE EFFECTS OF ACIDS

In 1891, Franz Hofmeister,¹the physiologic chemist of Strassburg, demonstrated that if disks of gelatin were brought into water and solutions of neutral salts, they gained less in weight in some solutions than in others. The inhibition of the swelling depended on the nature of the salt, tartrates, citrates, acetates, phosphates and sulphates, causing a greater inhibition than did chlorids, bromids and nitrates. In 1908, Martin H. Fischer²performed the same experiments, but added hydrochloric acid to the solutions, and in these acidulated solutions obtained results similar to the above-mentioned results of Hofmeister. Fischer performed his experiments not only with gelatin, but also with fibrin and numerous tissue colloids. He found the same conditions to apply to them all, namely, all the salts inhibited the swelling of colloids, which was brought about by immersing them in acids, and did so in about the order given by Hofmeister. Fischer

Evidence that the primary change in stimulation is an increase in the permeability of the limiting membranes of the irritable elements

Various facts and theoretical considerations indicate clearly that the process of stimulation in muscle or nerve has its seat at the semi-permeable boundary layers or plasma membranes of the irritable elements, and consists in a sudden and reversible increase in the permeability of these membranes. After a brief review of this general evidence the following experiments were described. I. Experiments with the Larvœ of Arenicola cristata.—These are the free-swimming ciliated larvæ of a marine annelid; they are small worm-like organisms about 0.3 mm. in length, readily obtained in large quantity by rearing. The larvæ have a well-developed muscular system; the special peculiarity which fits them for the purpose of the following experiments is the presence throughout the whole body of a water-soluble yellow pigment; this substance is contained within the cells, and does not visibly leave the latter except under conditions of markedly increased permeability—as on death or after treatment with cytolytic substances (e. g., saponin); it then diffuses into the medium and, if sufficient larvæ are present, colors the latter a bright straw yellow. Its exit thus serves as a convenient index of increased permeability. It was found that during strong chemical stimulation a rapid loss of pigment always occurs: the rate and degree of this loss run closely parallel with the intensity of the stimulating action, as indicated by the extent and duration of the muscular shortening. Pure isotonic (m/2) solutions of neutral sodium salts (NaCOOCH3, NaCl, NaBr, NaN03, NaCl03, NaI, NaCNS) all cause strong and persistent muscular contraction accompanied by rapid loss of pigment; the addition of a little calcium chloride to the solution (I C.C. m/2 CaCl2 to 25 C.C. m/2 sodium salt) prevents both the stimulating action and the loss of pigment.

ON EXTRACELLULAR AND INTRACELLULAR VENOM ACTIVATORS OF THE BLOOD, WITH ESPECIAL REFERENCE TO LECITHIN AND FATTY ACIDS AND THEIR COMPOUNDS

In normal serums of the majority of mammalian and avian blood there exists certain substances capable of activating venom haemolysin. They are extractable from serum by means of ether, and are capable of conferring upon the originally non-activating serum a power to activate venom, when mixed with the latter. The ethereal extract consists of fatty acids, neutral fats and possibly also some ether soluble organic soaps. The fatty acids and soaps, especially of the oleinic series, acquire certain characteristics of complements in general, when they are mixed with serum. They are inactive without the venom in the mixture; they are inactivable with calcium chloride; they exhibit a tendency to go off in activity with age; they are inactive or only weakly active at 0 degrees C., and they are extractable by ether. In testing the serum from which the ether soluble substances are removed, it is found that no venom activating property is left. Warm alcoholic extraction of such serum yields, however, a large quantity of lecithin. In the case of non-activating serums no venom activating fats appear in the ethereal extract. Lecithin exists in such serum in no less quantity than in the activating kind. The addition of oleinic acid or its soluble soaps to a non-activating serum, in a ratio which corresponds to the percentage of fatty acids or soaps contained in some of the easily activating serums, will make the serum highly active in regard to venom. In normal serum of dog there exists, besides the group of activators already mentioned, another kind of venom activators which has been identified as a lecithin compound acting in the manner of free lecithin. A very sharp differentiation of the haemolysis produced by this activator and by the other groups of activators is obtained by means of calcium chloride, which is powerless against lecithin or lecithin compounds, but effective in removing the action of the latter. This lecithin containing proteid can be precipitated by half saturation with ammonium sulphate, but is perfectly soluble in water, and is not coagulated in neutral alkaline salt solutions upon boiling. Alcohol precipitates a proteid-like coagulum and extracts lecithin from it; ether does not extract lecithin from this compound. Non-activating serums do not contain any such lecithin compound. Lecithin contained in other serum proteids, mainly as lecithalbumin, and perhaps as contained in globulin, is not able to activate venom. This is true of all the serums with which I worked; it matters not whether these fractions (obtained with ammonium sulphate) belong to the most activating serum (dog) or to the non-activating serum (ox). The non-coagulable portion of all heated serum contains a venom activator of the nature of lecithin. This activator is contained in a non-coagulable proteid described by Howell which is identical with Chabrie's albumon. As there is no ether-extractable lecithin in this portion of the serum, the activating property of heated serum must be due to this proteid compound of lecithin. That this lecithin proteid does not pre-exist in normal serum but is produced by the action of high temperature is true of all serums except that of the dog. In venom activation we know now that lecithin becomes reactive with venom when it is transformed from other proteid compounds into the non-coagulable form, the albumon. Howell's view of the non-existence of the non-coagulable proteid in normal serum seems to receive a biological support from venom haemolysis. Ovovitellin derived from hen's egg is one of the best venom activators of the lecithin proteid type. The cause of venom susceptibility of various kinds of blood corpuscles does not depend upon the existence of lecithin in the corpuscles, but solely upon the amount of fatty acids, and perhaps, also, soaps and fats, contained in the corpuscles. The protection which calcium chloride gives against venom haemolysis is proof of the absence of lecithin activation. From the stroma of susceptible corpuscles fatty acids or some fats can be extracted with ether. After ethereal extraction the stroma becomes non-activating, while the extract contains fatty acids and some soaps or fats, which when added to venom-resistant corpuscles render the latter vulnerable to venom. The corpuscular solution of non-activating corpuscles does not contain enough fatty acids. The larger the amount of fatty acids and soaps in the corpuscles, the easier the cells undergo venom haemolysis. Lecithin exists in the strorna of all kinds of corpuscles, but in a form unavailable for venom activation. The somatic cytolytic processes caused by venom requires intracellular complements. The experiments performed on the cells of liver, kidney, testis and brain of the guinea-pig and rat indicate that the substances which act as complements are inactivable by calcium chloride.

The chemistry of globulin

The object of the present paper is first to establish simple formulæ for the more important of the experimental results obtained by Hardy and Mellanby, then to interpret these in their bearing upon the chemistry of globulin in connection with a theory of colloids, and finally to find the molecular mass (weight) of globulin. The work will be taken according to the following table of contents. 1. Formula for the solution of globulin in solutions of neutral salts, and the laws associated with this formula. 2. Solution of globulin in acids and alkalies. 3. Formulæ for the precipitation of globulin by salts and by acids. 4. A theory of the colloidal state. 5. The electric conductivity of globulin solutions. 6. The molecular mass (weight) of globulin.

Scientific Serials

Wiedemann's Annalen der Physik tind Chemie, No. 7—Polarised fluorescence, by L. Sohncke. The polarisation of fluorescent light is capable of giving hints concerning the manner in which the molecules of a solid substance vibrate, and its study may form the basis of the kinetic theory of solids. Theoretically, all doubly-refracting crystals should emit polarised fluorescence. This is found to be the case. Crystals of the regular system are the only crystals which do not. The author has investigated the fluorescence of a large number of substances in confirmation of this view.—Uniformities in the spectra of solid bodies, by F. Paschen. The author investigates the distribution of energy in the spectrum of glowing iron oxide at various temperatures. Of the formula hitherto proposed for its expression, that of Weber most closely approaches the reality. It gives a nearly parabolic curve in which the energy declines on both sides from a maximum which decreases in wave-length as the temperature rises. But the want of symmetry in Weber's curve is greater than in reality. The author finds a new formula, for which he claims that it covers all the observations.—The electrical behaviour of vapours from electrified liquids, by G. Schwalbe. The author finds that the vapours rising from electrified liquids are not capable of bearing away with them any portion of the electric charge, and that Exner's theory of atmospheric electricity must therefore be abandoned.—The damping action of magnetic fields upon rotating insulators, by William Duane. Cylinders and discs of glass, sulphur, paraffin, ebonite, or quartz, oscillating between the poles of a magnet with their axes vertical and at right angles to the lines of force, experience a damping action proportional to the field intensity and to the speed of rotation. This is not due to an action on the suspending threads, nor on the viscosity of the air, nor an electrostratic effect from the current in the coils, nor to induction currents in the substance, as was proved by test experiments and calculations. It must therefore be regarded as a hitherto unobserved magnetic effect upon the insulators in question.—Effect of magnetism upon electromotive force, by A. H. Bucherer. The author finds that in solutions of neutral ferrous salts no E. M. F. exceeding 0˙00001 volt can be produced by the magnetisation of one of the two iron electrodes. The E.M. F.s observed by Gross and others must be attributed to changes of concentration produced by the magnetised electrode during its solution.—On the measurement of flame temperatures by thermo-elements, especially the temperature of the Bunsen burner, by W. J. Waggener. The temperatures were determined by various thermo-couples in different parts of the flame. The highest temperature, 1700°C., was indicated in the lower portion of the external mantle. But an infinitely thin thermo-element free from conduction would probably indicate over 17700°. A wire 0˙05 mm. thick still suffers from conduction, and it is actually fused in the hottest portion. A more refractory metal is required for these measurements.