摘要:

118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No.13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13. ON THE MEASUREMENT OF MECHANICAL PROd PERTIES OF BINARY INORGANIC SALT MIXTURES. BY K. LAYBOURN AND W. M. MADGIN. Received 4th October, 1932. In the following study of the mechanical properties of the three binary inorganic salt systems Pb(N03).,/NaN0,, Pb(N03),/KN03, and NaNOJKNO,! it has been found that, in addition to standardised con- ditions of casting and cooling of specimens, annealing and solvent treat- mcnt are of the utmost importance in obtaining consistent results. While Kurnakow and co-workers have measured Brinell hardness and pressure necessary to produce flow in certain binary mixtures of inorganic salts, they do not appear to have considered the possible effects of annealing such specimens.The present work was undertaken both as a study of the conditions necessary for consistent results and as a comparison of the properties of the three systems under review. Both of the binary systems involving Pb(NO,), have been shown to be of the simple eutectic type,, while NaNO, with KNO, forms a continuous series of solid solu- t i o n ~ . ~ A convenient means of comparing the systems and of examining the effects of solvent treatment is afforded by measurements of transverse breaking strength (the horizontal pull necessary to break a rod casting over two knife edges). Compression strengths also have been deter- mined for the system NaNO,/KNO,, and values have been obtained which show the effects of varying periods of annealing.In addition, Brinell hardness figures have been measured for all three systems, but it should be noted that both transverse breaking tests and compression tests possess certain advantages (discussed later) over determinations of Brinell hardness in the case of inorganic salts. Joff6 and Ewald * and Polanyi 5 have observed that the tensile strength of rock salt is greater under water than in air, and it seemed reasonable to suppose that atmospheric moisture might have a marked effect on the strengths of the castings used in the present work, since all the nitrates possess a considerable solubility in water. In the experiments now described it has been found necessary to treat all specimens with solvents to remove the effects of previous exposure, and to protect against sub- sequent attack by atmospheric moisture by coating the specimens with oil.Experimental. I. Transverse Breakiqg Strength. The specimen S (&-inch. diam. x 3&-inch long) is held loosely in a double collar C Apparatus.-This is shown diagrammatically in Fig. I. 2. anorg. Chem., 74, 89, 1912 : and earlier papers. Glass, Laybourn and Madgin, J. Chem. SOL, 874, 1932. Laybourn and Madgin, J. Chem. SOC., 2582, 1932. 2. PhySik, 22, 286, 1924. Trans. Faraday SOC., 24, 72, 1928. 857 56858 BINARY INORGANIC SALT MIXTURES (12 inches between collars), the inner surfaces of which are bevelled to ensure point contact only.A brass wire, attached to C, passes C # I ,1 FIG. I. as in tensile tests, and, in view of the brittle nature of salt castings, this is an obvious advantage. casting of Specimens.-The salts used in these and all other tests described were purified as stated by Glass, Laybourn and Madgin.2 The various mixtures used were synthesised by fusing together the appro- priate quantities of pure components in hard glass test tubes heated electrically. These melts were poured into gun metal split moulds which contained three separated circular casting holes (&inch x 3) inches), each provided with a feed trough to repair " pipes '' developed during setting. Cold casting was useless on account of premature setting of the melt with consequent irregular castings and coring.The moulds were therefore heated in an electric furnace packed with sand. It was also necessary to overheat the melts above the freezing-points so that (a) they did not set in the tube during pouring, and (b) extrusion of molten material within the moulds (resulting in winged castings) was avoided. The conditions finally adopted were : (I) KNO,!NaNO, mixtures : 1 Mould 100' below, melt 25" above F.P. of (2) { Pb(NOa)a/KNO, mixtures f melt. Pure sodium and potassium nitrates and the mixture of lowest freezing-point in each system were found to develop large " pipes " in the centre when setting, and feeding with melt was very necessary in these cases. Annealing and Solvent Treatment.--Widely varying results ob- tained with earlier castings suggested that annealing would be desir- able, and accordingly all rods were finally heated in close fitting glass tubes (to prevent distortion) for six days at temperatures roo below the Mould 75" below, melt 50' above F.P.Pb(NO,),/NaNO, and Castings were kept in desiccators pending testing. centrally through the knife - edges piece aa over the pulley p , to a spring balance B, which is in turn attached by a second brass wire, over pulleys p , and p,, to a screw wind- ing handle H . With the handle H a steady pull can be transmitted to C, and the specimen S then breaks in a uniform manner on the knife - edges. These knife - edges are 2 inches apart. In transverse breaking tests of this kind the speci- men does not re- quire to be grippedK. LAYBOURN AND W. M. MADGIN 859 minimum freezing-point in the appropriate systems.The freezing-point data are given by Briscoe and Madgin and Glass, Laybourn and Madgin.2 A specially constructed electric furnace was used to give uniform heating during annealing, and specimens were finally cooled off in the furnace. This annealing, resulted in greater consistency, but the values were stil1 conditioned by the time of exposure in the ordinary atmosphere between removal from the desiccator and testing. The effect of varying exposure to the atmosphere is shown by the following figures, obtained for seven annealed specimens of the same composition (45 per cent. KNO,, 5 5 per 20 2 bn .- I5 rd si 3 22 I0 3 E z C .I - M 0 : 5 0 Component A per cent. by weight. FIG. 2.-Transverse breaking strength/composition diagrams for the systems NaNO,/KNO,, Pb(NO,),/NaNO, and Pb(N08),/KN0,.cent. NaNO,). simultaneously, and tested consecutively in the order shown : The specimens were all removed from the dessicator Timeof exposure (mi-.) . o 5 10 15 20 25 30 Breakingstrength (lbs.) . 6 8 9-5 11.5 12.5 14.5 15 Believing these wide variations to be due to the effects of moisture, the following method of solvent treatment was adopted. Each specimen was dipped in distilled water to remove the effects of atmospheric mois- ture on the surface. The specimen was then dipped in alcohol and ether successively to remove the water, and, when dry, i t was dipped in medicinal paraffin oil ; this gave a protective coating from moisture, and J . Chem. SOC., 123, 1608, 1923.860 BINARY INORGANIC SALT MIXTURES adhered to the specimen during testing.Tests on specimens thus treated gave consistent and reproducible results, although the values were con- siderably lower than those for untreated specimens. The same degree of reproducibility was not attained, however, in the case of castings which had been treated with solvents, but had not been annealed, and i t is therefore evident that the conditions necessary for really satisfactory results are annealing, solvent treatment and surface protection. TABLE I .-EXPERIMENTAL DATA FOR TRANSVERSE BREAKING STRENGTHS (T.B.S.). (Compositions expressed as weight per cent. of the component stated.) Series I.-NaNO, with KNO,. 1bs. 8.5 11 12.7 13.3 13 10-3 7 5-8 4.5 3-7 4-2 5-2 7 6-9 6.5 6 4.8 Series 11.-Pb(NO,), with NaNO,.% NaNO, 40 45 47 50 55 57'7 60 65 70 75 80 85 90 95 T.B.S. in lbs. 7.5 8.5 7.7 6.5 1'75 1-25 1.5 3.7 3-9 3.7 3-5 3-2 2.8 2-5 Series 111.-Pb(NO,), with KNO,. The results of breaking strength tests on annealed and solvent Each treated specimens in the three binary systems are shown in Fig. 2 . value plotted was the mean of a t least six closely agreeing results. 2. Compression Strength. Apparatus.-Compression strength was measured with a 5-ton Buckton tensile machine, adapted for compression measurements, by determining the load necessary to crush each specimen. In the first series of experiments (referred t o as " continuous loading " experiments) the load was steadily increased until fracture occurred; in the second series (" intermittent loading " experiments), specimens were compressed at a series of increasing loads, each load being applied for thirty seconds, when it was released, and the length of the specimen measured with a screw gauge reading to OQOOI inch.Preparation of Specimens.-The specimens used were cast in cold Q-inch test-tubes, the casting melts being 25' above the respective freezing-points, and the test-tubes were completely filled. The middle portions of the thick rods thus obtained were sawn into suitable lengths, and these were trued up to I inch & 0.001 inch by polishing the ends on emery paper. Both annealed and unannealed specimens have been examined, and the annealing was done in closely fitting test-tubes under the same temperature conditions as with transverse breaking strengths.The usual solvent treatment with water, alcohol and ether was employed and the specimens were coated with paraffin oil. Only the system NaNO,/KNO, was examined by this method,K. LAYBOURN -4ND W. M. MADGIN 861 (a) Continuous Loading Experiments.-Under these conditions of loading a complete set of compression strengths has been determined for annealed specimens. Annealing for four days gave very consistent results, and in all cases the values were less than for unannealed speci- mens. Still lower compression strengths were obtained after fourteen days’ annealing, but the values were relatively the same as those for four days (Fig. 3), and i t is therefore concluded that the shorter period is sufficient. Figures obtained for unannealed specimens showed such specimens to be considerably stronger than those which had been annealed, but consistent crushing strength figures were not given.TABLE II.-COMPRESSION STRENGTHS (C.S.) FOR THE SYSTEM NaNO,/KNOs (Compositions expressed as weight per cent. of KNO,.) (a) Continuous Loading. I. Specimens annealed for 4 days. %moil * 0 10 25 40 55 70 85 IOO C.S. (lbs.) . . 320 1900 3700 2200 450 2100 1800 760 2 . Specimens annealed fov 14 days. yo KNO, . . o 1 0 25 40 55 70 85 IOO C.S. (lbs.) . - 1650 2600 1650 160 goo 750 - 3. Unannealed specimens. yo KNO, . 0 10 40 55 70 85 100 C.S. (lbs.) . . 350 2150 4800 1650 3700 3500 1100 (b) Intermittent Loading. Specimens annealed for 4 days. yo KNOs . 0 10 25 40 55 70 85 IOO C.S. (lbs.) . . 240 1700 3100 2000 290 1800 1300 580 (b) Intermittent Loading Experiments.-The length of each specimen, as measured after release of load, remained constant up to a small load (elastic limit), but thereafter a small but increasing permanent deformation occurred up to a certain load which varied with the com- position of the mixture.Beyond this point considerable plastic Aow set in and a further slight increase in load resulted in complete collapse of the specimen, the crushed material showing the typical cone-shaped fracture pieces similar to those obtained with crushed concrete. Fig. 4 summarises the data thus obtained. In all cases the final crushing strengths were markedly lower than those obtained in the parallel experiments under continuous loading (see Fig. 3). 3. Brine11 Hardness. Apparatus and Method.-The hardness figures for each of the three systems have been determined, using an “ Avery ” Hardness Testing862 BINARY INORGANIC SALT MIXTURES 0 25 50 75 I00 KNO, per cent.by weight. I. 4 days' annealing {continuous loading). 11. 4 days' annealing (intermittent loading). 111. 14 days' annealing (continuous loading). FIG. 3.-Compression strength/composition diagram for the system NaNO,/KNO,. TABLE III.-BRINELL HARDNESS FIGURES (B.H.). (Compositions expressed as weight per cent. of the component stated.) - ~ ~- Series I.-NaNO, with KNO,. yo KNO, . . o 10 25 40 55 70 85 IOO B.H. . . 3-0 13-1 28.2 25.8 1.6 28.2 14-3 8.8 Series 11.-Pb (NO,) with NaNO,. %NaNO, 90 85 80 75 70 65 60 57'7 55 50 45 40 B.H. . 10-0 11.8 13-7 16.7 19.4 16.7 11.8 8.6 17-4 18.8 19.4 17-4 Series III.-Pb(NO,), with KNO,.% KNO, * 95 90 85 80 75 70 65 60 55 50 45 40 35 B.H. . . 1.9 2-7 2-7 3-5 4.3 7-4 10.9 11.8 10.9 8-6 10.9 11.8 10.9K. LAYBOURN AND W. M. MADGIN 863 Machine by measuring the diameter of the impression made by a 10 mm. steel ball. Small loads, varying between 10 and 50 Kgms., were used, and the period of loading was 300 seconds. Specimens ( I inch diam. x 9 inch thick) were cast in cold nickel crucibles, and the melts used were poured a t 25' above the respective freezing-points. Both of the flat surfaces of the annealed specimens were polished parallel before testing. Solvent treatment was applied as 0 500 IOOO 1500 2000 2500 3000 Compression Ioad in lbs. weight. I. Pure NaNO,. V. 55 per cent. KNO,. VI. 70 per cent. KNO,.VII. 85 per cent. KNO,. VIII. Pure KNO,. FIG. 4.-Compression/load diagram for the system NaNO,/KNO, intermittent loading 11. 10 per cent. KNO,. 111. 25 per cent. KNO,. IV. 40 per cent. KNO,. experiments. before, but a paraffin oil coating was not applied, as it rendered the impression difficult to measure. Owing to the dull white colour and the softness of the material, the impression marks were not always well defined. In view of this and the fact that no protective oil coating was used, the same degree of precision and accuracy cannot be claimed for these tests as for transverse breaking strength and compression strength measurements. Nevertheless, Brine11864 BINARY INORGANIC SALT MIXTURES hardness evidently varies widely with composition, and the general nature of this variation is the same in all the three systems.Brine11 hardness was calculated from the formula : where : L = Load in Kilograms. D = Ball diameter (10 mm.). d = Diameter of impression in mm. The results are shown in Fig. 5 . o 10 20 30 40 50 60 70 8 2 Pb(NO,), per cent. by weight. M I. NaN03/KN0, 111. PblNO,),/KNO, 11. Pb NO,),/NaNO, I5 I0 5 0 100 go 80 70 60 50 40 30 20 10 o KNO, per cent. by weight. FIG. 5.-Brine11 hardness/composition diagrams for the systems NaNO,/KNO, Pb(NO,),/NaNO, and Pb(NO,),/KNO,. Discussion and Conclusions. It appears from the work now recorded that any examination of (a) Carefully regulated conditions of temperature for casting speci- (b) Adequate annealing of specimens. (c) Solvent treatment, followed by application of a protective oil The authors are of opinion that there are surface effects removed largely by solvent treatment, and volume effects, which can only be mechanical properties of inorganic salt mixtures demands : mens.coating.K. LAYBOURN AND W. M. MADGIN removed by annealing. I t may be expected that annealing would not only relieve the internal strains set up during cooling, but would also promote the well-known phenomena of grain-growth, with consequent weakening of the structure, and this would explain the fact that values for annealed specimens are always markedly less than those for un- annealed specimens. The surface effects have already been ascribed to the influence of atmospheric moisture. It is thought that such moisture may produce a recrystallisation film of fine crystals which has a cementing effect on the surface; solvent treatment would remove such a film.Minute surface cracks have been quoted as a source of weakness, and the increased strength of rock salt under water has,been explained by some as a result of the removal of such cracks.’ In the results now reported a pro- nounced weakening has been caused by solvent treatment, and it there- fore seems unlikely that the repair of surface cracks can be other than an insignificant factor by comparison with the cementation effects of atmospheric moisture. In the three systems examined, the results are evidently of the same general type, and do not afford a means to distinguish a eutectic from a solid solution system. The curves (Figs. 2, 3 and 5 ) are of the form which Kurnakow associates with partially miscible solid solutions, and in the case of the system NaNO,/KNO, this agrees with Tammann’s conclusion 8 that mixtures of these two salts segregate on cooling. How- ever, the two systems containing lead nitrate show behaviour somewhat different from that anticipated by Kurnakow, who has concluded that the property/composition curve should be a straight line for eutectic systems.In the present work, for certain intermediate mixtures values have been found which are much greater than would correspond with such a straight line relationship, although the actual eutectic mixtures have values very similar to those of the pure components. The authors find that the form of the curves is not altered by subjecting the specimens to as much as fourteen days’ annealing.The present results may possibly be explained in terms of internal strain. When mixtures of not exactly eutectic composition solidify, crystals of one pure component first separate and, a t a lower temperature, eutectic solid forms as a magma in which the primary crystals are em- bedded. The setting of the eutectic magma between the primary crystals would be expected to set up a condition of strain, with a resulting hardening effect in the solid mass.9 Such a hardening effect should reach a maximum for compositions lying between the eutectic composi- tion and the pure components, a conclusion which is amply supported by the results obtained in the present investigation. In the case of a solid solution system there are similar intermediate compositions of high internal strain where complete diffusion has probably not occurred on setting. In such a system, however, segregation in the solid state can take place on cooling, and in the resultant miscibility gap a condition of mere mechanical mixture is approached, with a corresponding weaken- ing of the structure.10 Unless segregation were quite complete, the two-peaked type of curve would thus persist. Cf. Desch, Trans. Faraday SOC., 24, 53, 1928. Cf. Sachs, 2. Metallk., 17, 85, 1925. * 2. anorg. Chem., IW, 65, 1931. lo Cf. Vrshesnevsky, J. Russ. Phys. Chem. SOL, 43, 1364, 1911.866 SURFACE TENSION OF MERCURY Summary. Transverse breaking strength, compression strength, and Brinell hard- ness figures have been measured for the systems NaNO,/KNO,, Pb(NO,),/ NaNO,, and Pb(NO,),/KNO,. Property/composition diagrams are of the same general form in all three systems, and an explanation of this, in terms of internal strains developed during crystallisation, is put forward. It is claimed that atmospheric moisture produces surface hardening which is removable by solvents. The special conditions of casting, annealing and surface treatment necessary to obtain consistent results are stated. We wish t o thank Professor C. J. Hawkes for facilities which enabled us to carry out Brinell and compression tests, and Mr. C. E. Pearson for his helpful advice. Armstrong College (University of Durham), Newcastle- upon - Tyne.

ISSN:0014-7672    

DOI:10.1039/TF9322800857

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No.13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.

ISSN:0014-7672    

DOI:10.1039/TF9322800866

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.

ISSN:0014-7672    

DOI:10.1039/TF9322800877

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.

ISSN:0014-7672    

DOI:10.1039/TF9322800885

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13. 890 THE BEHAVIOUR OF THE HYDROGEN ELECTRODE including the hydrogen and bright platinum electrodes in acid ferrous- ferric solutions. He showed that the hydrogen electrode behaved similarly to the bright platinum oxidation-reduction electrode and could be used to indicate the end points when a hydrochloric acid solution of ferrous and ferric chlorides was titrated with sodium hydroxide solution.The work to be described was undertaken to see whether the hydrogen electrode or the polished platinum electrode could be used to indicate the end-points when a sulphuric acid solution of chromous and chromic sulphates was similarly titrated with caustic soda. The following results show that broadly the effect is the same in both cases. In the case of the solutions studied, basic sulphates were probably precipitated and the inflections were not sharp enough t o give quantitative results, owing to the close proximity of the p H values of precipitation of chromous and chromic hydroxides, and the extreme instability of chromous salt solutions which slowly decompose water with the evolution of hydrogen at ordinary temperature^.^ The titration curves obtained, interpreted in the same way as Elder’s curves, enable an approximate value of the solubility product of chromous hydroxide to be calculated, a deter- mination which does not appear to have been previously attempted.Experimental. Preparation of the Solution. The chromous sulphate solution was prepared by electrolytic re- duction of chromic sulphate solution ( 4 9 3 ) . A lead cathode was used made from a rectangular piece of thin sheet lead, 10.5 x 7.4 cm. in size, bent into a cylindrical shape, with a tab for a terminal. This was thoroughly cleaned in moderately strong nitric acid and the surface prepared according to the instructions of TafeL6 This electrode was placed in a large porous pot, waxed to below liquid level and fitted with an air-tight waxed cork with two tubes passing through it, one to lead off the evolved hydrogen through a trap, the other to run off the reduced solution.The anode in the outer cell was of platinum gauze. A solution of chromic sulphate was prepared by stirring an excess of Kahlbaum pure crystalline chromic sulphate with water, in the cold, for some time and allowing it to stand. To IOO C.C. of this solution, 15 C.C. of concentrated sulphuric acid were added very slowly, the mixture being stirred and cooled in running water to avoid the formation of the green modification of chromic sulphate which is more difficult to r e d ~ c e . ~ The acid chromic sulphate solution was placed in the inner cell with 15 per cent.sulphuric acid in the outer cell. The liquid in the outer cell was covered with paraffin to keep air from diffusing through, and the whole was placed in a vessel of water kept cool by a spiral of lead pipe through which cold water flowed. A current of 0.7 amp. was passed through the solution for forty-five hours. At the end of this period some of the chromium salt had diffused through the pot, and becoming oxidised, coloured the solution orange, but the solution in the porous pot which was blown out and kept tightly stoppered under 4 inch. of paraffin, was deep blue. The concentration * Asmanov, 2. anorg. Ckem., 160, 209, 1927. 6 Tafel, 2. pkysakal. Chem., 34, 187, 1900. Traube, Burmeister and Stahn, 2. anorg. Chem., 147, 50, 1925.W. H. BENNETT of acid in the solution to be reduced appears high, but was adopted be- cause a similar reduction carried out with the same current density for the same time with 3 per cent.sulphuric acid, resulted in most of the chromium being deposited on the cathode as a hard irregular mass of mixed chromium metal and oxides. Analysis of the Solution. A portion of the solution was diluted with air-free distilled water and portions equivalent to z C.C. of the original solution taken for analysis. The total content of chromium and sulphate was determined by adding bromine water to oxidise the chromous salt to chromic, boiling off the excess bromine and precipitating chromic hydroxide with ammonia in the presence of ammonium chloride in the usual way; dissolving the precipitate in hydrochloric acid, reprecipitating with the addition of some macerated filter paper, washing and igniting the precipitate to Cr,O,.owing to the formation of higher oxides of chromium. In these cases the precipitated hydroxide had been dried and ignited, without the addition of filter pulp which would cause the ignited oxide to be hard and lumpy. It was found, however, that precipitation in the presence of filter pulp and subsequent slow ignition yielded a fine powdery oxide of theoretical composition, The filtrates obtained above were combined, adjusted to an acidity of 24 per cent. with hydrochloric acid and the sulphate precipitated with barium chloride, allowed to settle overnight, filtered, ignited and weighed as BaSO,. To determine the chromous content of the solution a portion was quickly pipetted into an excess of ferric alum solution acidified with sulphuric acid, and the ferrous iron formed titrated with standard potassium permanganate solution which had been standardised against A.R.ferrous ammonium sulphate. The colour of the chromium salts obscured the end-point to some extent, but if the titration was carried out in a beaker held a few inches above a brightly illuminated white tile the end-point was easily visible and readings agreed exactly with those obtained by potentiometric titration of the same solutions. I t was found that z C.C. of the reduced chromium solution contained 0-ogz I gm. of chromous chromium and O*OIZZ gm. of chromic chromium. This solution had to be standardised each time before use as i t slowly oxidised, even in a stoppered bottle under 4 inch of paraffin.For instance, after twenty days, 2 C.C. of the above solution contained 0.0886 gm. chromous chromium, and after fifty days, 2 C.C. of the same solution contained -0788 gm. chromous chromium. This method has been stated to give high results Titration. The titration cell was a wide-mouthed bottle, fitted with a waxed air-tight cork bored for the hydrogen or oxidation-reduction electrode, hydrogen exit, burette, stirrer, auxiliary electrode and hydrogen entrance, the latter being used only when the oxidation-reduction electrode was in use. The stirrer had a mercury seal so that the cell could be com- pletely filled with hydrogen and remain air-tight. The hydrogen electrode was of the wire type, consisting of a piece of platinum wire sealed into the end of a thin glass tube and wound round the outside.6 See H. T. S. Britton, Analyst, 49, 130, 1924.892 THE BEHAVIOUR OF THE HYDROGEN ELECTRODE of the tube five or six times. The electrode was mounted in a wider tube down which hydrogen was blown so that 2 or 3 mm. of the spiral projected. It was platinised according to the instructions of Britton 7 and checked against a phthalate buffer. This electrode was more convenient for this cell than the foil type and was quite satisfactory as long as the spira! was not allowed to project far out of the end of the tube, as slightly lower readings were then obtained, owing no doubt to the end of the wire becoming unsaturated with hydrogen. When i t was adjusted so that only 2 or 3 mm.of the tip of the spiral projected into the liquid results were very reliable. The oxidation-reduction electrode was of bright platinum gauze and was thoroughly cleaned before each determination. A saturated calomel electrode connected by a saturated potassium chloride bridge was used as an auxiliary electrode. The E.M.F. was measured by the potentiometer-voltmeter method.8 The scale of the voltmeter was only graduated in centivolts but the E.M.F. could be estimated to within 2 millivolts, which is quite accurate enough for work on unstable solutions of this type. The solution to be titrated was made by adding 5 C.C. of the stock chromous-chromic solution t o 100 C.C. of air-free water, and duplicate solutions were titrated with 0.9111 N / 5 NaOH with the hydrogen and bright platinum electrodes, the cell being filled with hydrogen.The solution was stirred after the addition of each portion of alkali, but not while the readings were being taken. The time taken to reach equilib- rium varied from three to ten minutes, being greatest near the inflection points. Light green chromic hydroxide was precipitated first, followed by brownish-black chromous hydroxide. The point a t which chromic hydroxide began to precipitate was easily noted by the appearance of a permanent turbidity in the solution and the commencement of the precipitation of chromous hydroxide was made evident by the blacken- ing of the precipitate produced round each drop of caustic soda solution added. The titration cell was strongly illuminated from behind so as t o make these changes easily recognisable.Owing to the instability of the solution its composition could not be kept constant and the curves exactly duplicated, but they were all the same shape and the general results obtained from each were similar. The one reproduced is typical of the series. The solution used in obtaining this curve contained 0.221 5 gm. chromous chromium, 0.0368 gm. chromic chromium and 0.3214 gm. SO, in 105 C.C. From this the theoretical end-points of the titration were calculated as 33'43 c.c., 45.08 c.c., and 91-86 C.C. of 0.91 I I N / 5 NaOH. The three vertical dotted lines X, Y and 2, in the diagram, correspond to these end-points and the two arrows indicate the points a t which chromic and chromous hydroxides began to be precipitated.The slope of that portion of the curve corresponding to the precipitation of chromous hydroxide is greater than would be expected from theory. I t is notable that the slopes of the curves obtained by Britton and Elder for the precipitation of Fe(OH), are abnormal, but no explanation of this effect is offered. In the present case the close proximity of the pre- cipitation p , values of Cr(OH), and Cr(OH), would no doubt influence the shape of the curve, as the two hydroxides might be precipitated H. T. S . Britton, Hydrogen Ions, p. 35, 1932. 8 Sand and Law, J . SOC. Chem. Ind., 30, 3872, 1911. *H. T. S. Britton, J.C.S., 127, 2110-215g, 1925. A number of titrations were carried out.W. H. BENNETT 893 together near the inflection point.Again the explanation may lie in the disturbances in the E.M.F. of the hydrogen electrode due to the tendency of chromous salts to decompose with evolution of hydrogen, a reaction which is catalysed by platinum black.3 In both cases t h e divergence from the true value would be less as the [Cr"] diminished. I t will be evident from the shape of the curve that the end-points can only be roughly fixed by its aid. The first two inflections, giving the neutralisation point of the free sulphuric acid and the completion 20 X 40 Y 60 80 Z 100 ccs. N / 5 NaOH Hydrogen Electrode. Temperature 18" C. _ _ _ - - - - - Bright Platinum Electrode. FIG. I. of the precipitation of Cr(OH),, agree approximately with the theoretical, but Cr(OH), required much less than the theoretical amount of NaOH to complete the precipitation.This points to the precipitation of a basic sulphate. Britton notes the precipitation of basic sulphates by the action of dilute NaOH on many metallic salt solutions. states that this does not take place in the case of ferrous and ferric chloride solutions although Britton had previously obtained evidence of the precipitation of basic sulphates from both ferrous and ferric sul- phate solutions. Elder894 THE BEHAVIOUR OF THE HYDROGEN ELECTRODE [Cr":. * E Cc. of NaOH Short of Equivalence Volume. 4 C.C. 2-64 x 10'~ 5.59 8 C.C. 5-40 x I O - ~ 5-40 I2 C.C. 8.30 x I O - ~ 5-27 *OH [OH-]. [Cr,*7[OH-]? -- 8-54 -288 x I O - ~ 2-20 x IO-w) 8.73 -186 x I O - ~ 1-88 x I O - ~ O 8-86 -130 x I O - ~ 1-67 x IO-~O The solubility product of Cr(OH), can thus be taken as approximately 2.0 x I O - ~ at 18" C.The p~ of precipitation of Cr(OH), from the above dilute solutions which may be taken as 5-6 is very close to the initial p , of precipitation of Cr(OH), which is given by Britton as 5.3 and this would account to some extent for the badly-defined inflections in the titration curve. The Calculation of Solubility Products from Titration Curves. Brittons obtained a number of curves for the titration of metallic salt solutions with alkali and calculated solubility products of the hydroxides from these, which, he stated, were in good agreement with values already obtained by other workers, although the precipitated hydroxides were often basic. SweeneylO used Britton's data for the solubility product of Fe(OH), and recalculated the result.Elder lo Sweeney, Trans. Arner. Elect. SOC., 53, 324. 1928.W. H. BENNETT 895 quotes Sweeney's figures, criticises Britton's method of calculation and suggests that the points on the curve from which the solubility product data were to be obtained, should be those recorded a t the end of the titration when the [Fe"] is relatively low and not a t the beginning of the titration where Britton's figures were obtained. Elder thus ob- tained values for [Fe"][OH-]2 ranging from 2-3-9.7 x 10-l~. It is evident also that the use of readings taken at the end of the titration will help to eliminate errors due to the hydroxide or basic oxide being first present in the colloidal state before actual precipitation takes place.Britton has since l1 calculated solubility products of Fe(OH), from data obtained over the entire range of precipitation and these vary progressively from 9 x 10-l~ to I x 10-l~. He now states, arguing from this, a similar variation in the case of Pb(OH), and in a lesser degree C,(OH), that the solubility product principle is untenable in the case of the formation of basic precipitates generally, although it appears to hold in the precipitation of Ag(OH),. This statement appears to be rather sweeping as even in the cases of the precipitation of Mg(OH),, Mn(OH),, Ni(OH),, Cu(OH), and Al(OH), from sulphate solutions, where basic sulphates are undoubtedly formed, the solubility product calculated from the precipitation curve at the end of the precipitation is never more than ten times the value a t the beginning of the titration, in spite of the fact that the system could hardly have reached equilibrium during the comparatively short period required for a titration.It is significant that although Britton's values for [Fe"][OH-I2 vary so widely the value which he obtained a t the end of the titration, i.e., I x 10-l~ is more consistent with other published values which range from 1-64 x 10-l~ to 4-8 x 10-16,12 excluding Britton's previously published values and Sweeney's recalculation of them, than the value of g x 10-l~ obtained at the beginning. Having regard to the above the solubility product of Cr(OH), was calculated from data obtained a t the end of the titration and the product obtained is approximately constant.Summary. ( I ) Sulphuric acid solutions of chromous and chromic sulphates have been titrated with caustic soda, using the hydrogen and bright platinum electrodes as indicator electrodes. Inflections in the hydrogen electrode titration curve corresponding to the three stages of neutralisation of the alkali are obtained, but these are not sharp enough for quantitative purposes. ( 2 ) The hydrogen electrode has been found t o behave as an oxidation- reduction electrode governed by the Cr"/Cr"' equilibrium until Cr(0H) s is completely precipitated, after which it behaves normally. (3) The PH of precipitation of Cr(OH), from very dilute solutions of CrSO, has been found t o be 5-6 and from this the solubility product of Cr(OH), has been calculated.The author wishes to express his thanks to Dr. H. J. S. Sand for Sir rohn Cass Technical Institute, his interest and advice during the course of this work. London, E. C. 3. l1 H. T. S. Britton and R. A. Robinson, Trans. Favad. Soc., 28, 541, 1932. l2 Randall and Frandsen, J . Amer. Chem. Soc., 54, 46, 1932.W. H. BENNETT 895 quotes Sweeney's figures, criticises Britton's method of calculation and suggests that the points on the curve from which the solubility product data were to be obtained, should be those recorded a t the end of the titration when the [Fe"] is relatively low and not a t the beginning of the titration where Britton's figures were obtained. Elder thus ob- tained values for [Fe"][OH-]2 ranging from 2-3-9.7 x 10-l~. It is evident also that the use of readings taken at the end of the titration will help to eliminate errors due to the hydroxide or basic oxide being first present in the colloidal state before actual precipitation takes place. Britton has since l1 calculated solubility products of Fe(OH), from data obtained over the entire range of precipitation and these vary progressively from 9 x 10-l~ to I x 10-l~.He now states, arguing from this, a similar variation in the case of Pb(OH), and in a lesser degree C,(OH), that the solubility product principle is untenable in the case of the formation of basic precipitates generally, although it appears to hold in the precipitation of Ag(OH),. This statement appears to be rather sweeping as even in the cases of the precipitation of Mg(OH),, Mn(OH),, Ni(OH),, Cu(OH), and Al(OH), from sulphate solutions, where basic sulphates are undoubtedly formed, the solubility product calculated from the precipitation curve at the end of the precipitation is never more than ten times the value a t the beginning of the titration, in spite of the fact that the system could hardly have reached equilibrium during the comparatively short period required for a titration.It is significant that although Britton's values for [Fe"][OH-I2 vary so widely the value which he obtained a t the end of the titration, i.e., I x 10-l~ is more consistent with other published values which range from 1-64 x 10-l~ to 4-8 x 10-16,12 excluding Britton's previously published values and Sweeney's recalculation of them, than the value of g x 10-l~ obtained at the beginning. Having regard to the above the solubility product of Cr(OH), was calculated from data obtained a t the end of the titration and the product obtained is approximately constant. Summary. ( I ) Sulphuric acid solutions of chromous and chromic sulphates have been titrated with caustic soda, using the hydrogen and bright platinum electrodes as indicator electrodes. Inflections in the hydrogen electrode titration curve corresponding to the three stages of neutralisation of the alkali are obtained, but these are not sharp enough for quantitative purposes. ( 2 ) The hydrogen electrode has been found t o behave as an oxidation- reduction electrode governed by the Cr"/Cr"' equilibrium until Cr(0H) s is completely precipitated, after which it behaves normally. (3) The PH of precipitation of Cr(OH), from very dilute solutions of CrSO, has been found t o be 5-6 and from this the solubility product of Cr(OH), has been calculated. The author wishes to express his thanks to Dr. H. J. S. Sand for Sir rohn Cass Technical Institute, his interest and advice during the course of this work. London, E. C. 3. l1 H. T. S. Britton and R. A. Robinson, Trans. Favad. Soc., 28, 541, 1932. l2 Randall and Frandsen, J . Amer. Chem. Soc., 54, 46, 1932.

ISSN:0014-7672    

DOI:10.1039/TF9322800889

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13. STUDIES IN ADSORPTION. PART 1.-ADSORPTION OF CARBON DIOXIDE, SULPHUR DIOXIDE AND WATER. BY R. C . BOSWORTH (University of Adelaide). Communicated by E. K. RIDEAL. Received 25th October, 1932. In 1927 M. L. Oliphant,l working in this laboratory, measured the number of C02 molecules adsorbed on mercury from excess of both hydrogen and argon.His results led to the conclusion that the ad- sorbed layer is monomolcular and that the film is practically complete when the gas phase contains 2 per cent. or more of carbon dioxide. The method and apparatus employed in the present work is, with certain modifications, the same as that used by Oliphant and may briefly be described as follows : Pure mercury fell in fine drops (0.1 mm.) down a vertical cylindrical tube. At the centre of this tube the gaseous mixture was introduced and divided into two streams one issuing from the top, the other from the bottom. Thus the downward stream was enriched by liberation of the gas molecules adsorbed on the falling mercury, and the upwards stream correspondingly impoverished. The two streams were subsequently taken through the double tube of a Rayleigh refractometer capable of indicating a change in refractive index of I in 10'.This change in refractive index was measured by a compensating device and from its value the percentage composition of the gaseous streams could be deduced. The mercury passed by means of a syphon from the bottom of the adsorption tube to a lower vessel from which it was pumped back to a reservoir supplying the shower. Circulation of the gas under investigation was maintained by means of a Sprengel pump. An earthed metal shield placed around the shower- head which helped to prevent electrification of the drops, was found necessary in some of the investigations. Method of Working. Both before commencement, and a t various intervals throughout these experiments, the apparatus was thoroughly washed in warm chromic acid mixture, steamed out until all acid had been removed, rinsed in distilled water and dried in a stream of warm dry air. The mercury, in the first place, was purified by the method described by Burdon,2 and during the experiments was washed from time to time either in distilled water, or very dilute mercurous nitrate, followed by distilled water.The gas mixtures, in the first place consisting of C02 and air, were admitted through a drying tube and circulated by means of the Sprengel 1 Oliphant, Phil. Mug. (Sr. 7). 6, 422, 1928. a Burdon. PYOC. Physic. SOC., Lond., 38, 148, 1926. 896R. C. BOSWORTH 897 pump with the shower running until the interference fringes in the interferometer showed no further tendency to move.The shift of the fringes was then read and the composition of the gas deduced there- from. From this and from a knowledge of the area of mercury surface falling per second, obtained by stroboscopically counting the drops and by measuring the weight of mercury which flows through the apparatus in unit time; together with a knowledge of the rate of flow of the gas; the adsorption per square centimeter could readily be computed. Measurements on sulphur dioxide were obtained in a precisely similar way. In all these determinations a drying tube containing glass wool soaked in strong sulphuric acid was included in the gas circuit. In later experiments this drying tube was omitted and wet gases were used. Experiments on mixtures of air and carbon dioxide con- / A = CO, from dry hydrogen (Oliphant).B = SO, from dry air (Bosworth). C = CO, from dry air (Bosworth). FIG. I. taining small amounts of water vapour indicated an adsorption which was definite but considerably less than that obtained with dry gases. This led to the use of a katharometer in series with the Rayleigh re- fractometer, enabling the variation in the composition of the two streams of gas with respect to two unknowns to be determined, and thus per- mitting a calculation of the number both of CO, and H20 molecules absorbed to be effected. Further experiments were carried out on mixtures of CO, and SO, and of SO, and H20. Results. Let us represent the number of carbon dioxide molecules adsorbed on one square centimeter by NQ, etc., and the percentage composition of the gas by etc.898 CARBON DIOXIDE, SULPHUR DIOXIDE AND WATER cco,.Nso2 . 10 - 1'. 0-4 2'2 1'7 5'2 0.8 4'4 The results for adsorption of CO, and SO, from dry air are shown on Fig. I where NCO, is plotted against log CCO, and N w , against log Cso,. Oliphant's points for CO, from dry hydrogen are added for comparison. Figs. 2 and 3 gives the corresponding adsorption from moist air, the percentage of water vapour present being stated against each curve. The graphs for the total number of molecules adsorbed are shown as the dotted curves-these approximate to horizontal straight lines, i.e. the total number of adsorbed molecules appears to be independent of the relative concentrations of the constituents.NCO, . I0 - 14. - 1.7 0.3 1.1 Logarithm of Compositim A = Total number of molecules adsorbed CO, + H,O. B = Number of H,O molecules adsorbed (1.4 per cent. H,O and varying amounts C = CO, from air containing 0.6 per cent. H,O. D = CO, from air containing 1'2 per cent. H,O. of CO,). FIG. 2. The following results are not shown on the graphs : - AIR, CARBON DIOXIDE, SULPHUR DIOXIDE MIXTURES. cso,. 1'2 2'9 5'4 cH*O. R O , + NSOI) * I0 - 14. 3'9 5'5 5'5 NH20. When working with saturated vapours no concordant results could be obtained, suggesting that the adsorption of a saturated vapour on an expanding mercury surface is quite an indefinite reaction. ThisR. C. BOSWORTH 899 agrees with the conclusion of Iredale,3 that the surface tension of mercury is quite indefinite in the presence of a saturated vapour.In the experiments on sulphur dioxide, there was strong evidence for the occurrence of some reaction other than pure physical adsorption between the SO, and the expanding mercury surface, for on running the apparatus, all tubes through which mercury passed, became coated on the inside with a whitish deposit. This deposit appeared most copiously a t places where the adsorbed molecules were liber- ated, vix., a t the bottom of the dropping chamber and of the Sprengel qump. On examina- tion this film appeared to be composed mainly of amorphous sulphur. Further the mercury surface was affected in such a way that a drop of distilled water would spread rapidly across the surface of a sample 0.5 1 0 Logarithm of Composition PO -I- A = Total number of molecules adsorbed SO, + H,O.B = H,O from air, 1.2 per cent. H,O and varying amount C = SO, from air containing 1-2 per cent. H,O. of so,. FIG. 3. withdrawn from t h i apparatus. These observations lead to the con- clusion that the mercury surface catalytically reduces part of the adsorbed SO, and permanently entrains some acidic or quasi-acidic reaction-product. All of the experiments described in this paper were carried out in an underground room, the temperature variations of which fell within the limits 15.0~ C. to 16.5" C. Discussion of Results. Before commencing the experiments described in this paper, the instrument was set going with only dry air, freed from carbon dioxide, in the circulating system-no evidence of variation in composition was obtained.This must not be taken to imply that there is, for example, no selective adsorption of oxygen from nitrogen, since both the refractive indices and the thermal conductivities of these two gases are so nearly equal that the instruments used would only indicate large changes in oxygen or nitrogen content. It is known that oxygen is selectively adsorbed by such a metal as tungsten and Heyrovsky and Simunck4 also believe by mercury. These two authors used the hy- pothesis of an adsorbed oxygen layer to explain the Kucera anomalies in the electro-capillary curves for mercury. These Kucera anomalies Iredale, Phil. Mag. (Ser. 6), 48, 177, 1924. Heyrovsky, Phil. Mug. (Ser. 6), 45, 303, 1923 ; and Simunck, ibid. (Ser. 7), 7 9 951, 1929.goo CARBON DIOXIDE, SULPHUR DIOXIDE AND WATER consist in a discontinuous fall in the surface tension of a polarized mercury electrode, near the peak of the electro-capillary curve.It may perhaps be said in criticism of these experiments that the mercury surface falling through the active gas does not remain in con- tact with i t long enough for adsorption to be complete. For Popesco5 has determined the surface tension of mercury in contact with various gases, and, finding a progressive change in the surface tension extending over twenty-four hours or more, infers that the mercury slowly comes into adsorptive equilibrium with the gas. MittonYg on the other hand, has shown from kinetic principles that adsorptive equilibrium must be reached in less than &-o second, a conclusion in accord with the theories of Langmuir.In the experiments just described, the drops of mercury are in contact with the gas for about second. This time c t - .- 3 0 - 1 I 1 1 I Logarithm of Composition A = CO, from dry H,O. B = SO, from dry air. C = CO, from dry air. D = CO, from air containing 0.6 per cent. H,O. E = CO, from air containing 1.2 per cent. H,O. FIG. 4. should be ample to allow for attainment of equilibrium in the adsorbed layer. As a matter of fact one would rather expect that the adsorption would be complete before the original random distribution of the mercury molecules a t the newly formed surface could be destroyed by orienta- tion. In other words, this method studies adsorption on a dynamic and not an equilibrium and oriented surface.Calculation of the number of carbon dioxide molecules required to. form one square centimeter of a monomolecular layer on the assumption that this layer has the same bulk density as liquid C02, shows that some. 5.6 X lol* molecules are required. Comparing this figure with the one found experimentally above shows that the gases studied give mono- molecular layers which are close-packed when the air contains I per. Popesco, Ann. Physique (Ser. IO), 3, 4, 1925. * Mitton, Trans. Roy. SOC. of S.A., 53. 267, 1929.R. C. BOSWORTH 901 cent. or more of the capillary active gas. Where mixed gases are used the total layer is monomolecular and introducing more molecules of one type means displacing molecules of the other type, molecule for molecule, in a way which is reminiscent of the displacement type of chemical reaction. Application of Gibb's Equation.The approximate form of this equation most useful when dealing with gases is I du RT d l n p ' r=-- - Where I' is surface excess concentration, R the gas constant, T the absolute temperature, u the surface tension, p the partial pressure due to the active gas. and Expressing this equation in terms of molecular, not molar, quantities we get I du RT d l n p ' a=--- Where k is the Boltzmann gas constant and n the number of molecules adsorbed, the integral form of the above equation is ~1 - U, = 2'303 kT J nd(log p ) , or, the decrease in surface tension below the dynamic value produced by CO, (or SO,) should be equal to 2-303 kT multiplied by the area enclosed by the n - log c curve, the x axis and the ordinate log c = 2 .u1 - u, = 116 for CO, = 136 for SO,. Taking T as 287 we get The second figure is possibly far too low, as the chemical reaction between the mercury and the sulphur dioxide can only mean that every Nso, is an underestimate. The above figures may be compared with actual measured surface tension lowerings produced by CO, and SO,. Popesco's5 figures, for example, show that the difference between the values finally attained in Cog and the extrapolated value of a freshly formed drop is 130 dynes per centimetre and the corresponding figure for SO, is 213 dynes. Cook's determination of the surface tension lowering produced by CO, gave 88 dynes per centimetre. Application of the Freundlich Isotherm. xlm = a P This equation is given in the form Where x is the amount adsorbed, m the mass of the adsorbent, C the equilibrium concentration, and a and b are constants.Cook, Physic. Rev. (Ser. 2), 34, 513, 1929.902 CARBON DIOXIDE, SULPHUR DIOXIDE AND WATER Applied to the case in hand it indicates a relationship of the type naC1lb The results of plotting log n against log c are shown on Fig. 3. or a linear relationship between log n and log c. curves for dry CO, and SO2 consist of two linear sections. linear portion of each of these curves has a slope - =') and a t a point log c = I , i.e. for a gas containing I per cent. of either COz or SO, this changes abruptly to a slope of only &. Oliphant's few figures (CO, from H,) may be interpreted as giving a curve of the same general type with the point of discontinuity a t a somewhat higher value of log c.The values obtained for CO, adsorbed from moist air also gives straight lines whose slopes approximate to Q, making i t appear that, as long as the adsorbed layer is not saturated with molecules of the component under consideration (with dry gases the monomolecular layer was not complete below I per cent.), then the relation between the number of molecules of that given component in the adsorbed layer and the number of the same molecular type in the atmosphere above, is of the form: narc#. This relation implies that the number of molecules of the given kind present on unit area on the mercury surface is proportional to the number in the sectional area of the gas above the mercury. The most obvious interpretation of this result would seem to be that we are here concerned with a two-dimensional type of Kinetic Equilibrium. No such type, however, appears to have been contem- plated by theoretical workers on adsorption. The The lower d log n (dlogC b Of Summary. Using a Rayleigh Refractometer to measure the small changes in composition produced when a shower of small drops of mercury falls through a column of mixed gas, it is found that : (I) CO,, H,O and SO, are all selectively adsorbed on the mercury surface. ( 2 ) The layers are confined to monomolecular. (3) The time taken for complete adsorption is certainly less than 4 second. (4) When the gaseous phase contains two active gases the adsorbed phase also contains these two components in relative proportions which increase with the relative concentrations. (5) The total number of adsorbed molecules corresponds to a complete monomolecular layer and is independent of the relative concentrations of the active gases. (6) For a layer not saturated with the given component the relation between n and c is nccc8. In conclusion the author would like to express his sincere thanks to Professor Kerr Grant and to Mr. R. S. Burdon for the interest they have taken in this work, and for the many ways in which they have helped the author carry it out. Physics Department, University of Adelaide, 5th September, 1932.

ISSN:0014-7672    

DOI:10.1039/TF9322800896

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.

ISSN:0014-7672    

DOI:10.1039/TF9322800903

出版商:RSC    

年代:1932

数据来源: RSC

摘要:

118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point.These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No.13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions.Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order.The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure.This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility.The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.118 ELECTRICAL THEORY OF ADBORPTTON The writer considers the double layer as consisting of a swface of rigidly fixed atoms under continuous bombardment of positively and negatively charged ions, any particular point on the rigid surface becoming in turn negative, neutral and positive, these conditions arisdg in any order. The observed contact difference is the average effect of these conditions. Where several kinds of atoms are present in the solution the average number of any one of them at the surface will depend on their concentbration, valency and mobility. The variation of contact Werence from negative to neutral and positive was observed with cotton and aluminium sulphate near the neutral point. These variations occurred during the same experiment, the readings being direct measurements of E.1I.F.s developed by filtration under pressure. This point would be covered by putting n2 = 1 and = 2 or 3 in Mukherjee’s equation No. 13.

ISSN:0014-7672    

DOI:10.1039/TF9322800912

出版商:RSC    

年代:1932

数据来源: RSC