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.

ISSN:0014-7672    

DOI:10.1039/TF93026FP001

出版商:RSC    

年代:1930

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.

ISSN:0014-7672    

DOI:10.1039/TF93026BP007

出版商:RSC    

年代:1930

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. STUDIES ON HYDROGEN OVERPOTENTIAL BY THE DROPPING MERCURY CATHODE.BY WILLIAM VERNON LLOYD, hl.Sc., A.I.C. (Received I 9th September, 1929.) Using the mercury dropping cathode, Heyrovskyl has shown that the overpotential of mercury varies logarithmically with the current producing the overpotential. Ifw is the overpotential and i the current, dwJd log i (i.e., the increase in overpotential for a tenfold increase of current) has been determined in acid solution by Merasymenko,2 who found 0.087 volt apparently for all hydrogen ion concentrations. In his experiments, the current density was approximately constant, current variation being due to the growth of the drops. and Bowden and Rideal,4 using the direct method on a stationary mercury surface, and also the dropping electrode with current approxi- mately constant, i.e., with variation of current density during the growth of the drop, showed that for the metals studied in acid solution, dwld log i had two values: (a) 0.22 volt for that part of the curve studied by Herasymenko; ( b ) 0.120 volt for very small current densities.As regards the effect of composition of the electrolyte for a given current density, in case (a) the change in overpotential was equal to the change in p , voltage,* whilst for (b) the overpotential was independent of the p , voltage. Bowden and Rideal examine overpotentials on other metals previously studied by Tafel,5 who found for mercury in 2N H,S04 dwld log i = 0.102. The present work was undertaken to elucidate the discrepancy between the results of Herasymenko and those of Bowden and Rideal and particularly to investigate the value of dw/d log i for the dropping mercury cathode using hydrochloric acid alone and in conjunction with potassium chloride and potassium hydroxide solutions.Bowden Experimental. The experimental arrangement was similar to that used by Heyrovsky.6 The cell was a conical flask of 100 C.C. capacity. The electrolysing E.M.F. was taken from two sliding contacts on a resistance, to the ends of which 6 volts were applied. This electrolysing E.M.F. was increased by a centrivolt at a time and the current noted by means of a mirror galvanometer suitably shunted to read up to 3.6 x I O - ~ amp. in units of 6 X I O - ~ amp., or up to 27.7 x I O - ~ in units of 4-6 x 10"~ amp. Pure hydrogen was bubbled through the electrolyte for a t least 30 Rec.Tmv. Chim., 44, 488, 1925. 3 Tvans. Farad. SOC., 24,473, 1928. Proc. Roy. Sor., A. 120, 59, 80, 1928. 2. physik. Chem., 50,641, 1905. * The p~ voltage of a solution is defined as the potential difference between 2. Elektrochem., 34, 131, 1928. Phil. Mag., 45, 303, 1923. a hydrogen electrode working in that solution and a standard half element. I2w. v. LLOYD I 3 minutes before each experiment. For any applied E.M.F., the current increases with each growing drop and then falls to a smaller value as the drop leaves the capillary, as already known from work published by Heyrovsky. Superimposed upon this effect there is, however, a gradual growth of the current to a maximum, which takes up to about 2 minutes, the variation of the current during the growth of a drop amounting to about 7 per cent., that taking place with time for each applied E.M.F.amounting to about 50 per cent. For very small current densities, no oscillations were noted : Heyrovsky is of opinion that this shows that the solution is free from reducible material. The overpotentials for these very small currents do not vary loga- rithmically with the current and are not considered in the present paper. Except where otherwise stated, the maximum current for any applied E.M. F. was measured. Owing to the anodic potential of the mercury being constant and the P.D. due to ohmic resistance in the electrolyte being negligible, the applied P.D. is a measure of the cathodic overpotential, the former being the latter plus a constant for any one experiment. Results.I . It was confirmed that the overpotential varies logarithmically with the current except with the lowest and highest currents used. In the case of the latter, deviations due to concentration effects were pronounced in the more dilute solutions. Only the strictly logarithmic portions of the E.M.F./current have been considered. 2. Tables I., 11. and 111. give the values for dw/d log i in varying strengths of pure HCl, pure KC1 and KOH diluted with N/IO KC1 solu- tions respectively, w being the overpotential. The dropping times are given in each case. TABLE I.-PuRE HC1 SOLUTION. 4-3 SEC. DROPS. Strength N/4 N/32 N/64 N/128 AT/256 N/512 NI1024 dwldlogi 0.105 0.115 0.126 0.134 0.146 0.162 0.158 TABLE IL-PuRE KC1 SOLUTIONS. 4-3 SEC. DROPS. Strength N N/4 NIIO -v/16 N/4o N/160 N/640 dw,/dlogi 0.066 0.081 0.083 0.087 0.105 0.128 0.184 volts.TABLE 111.-KOH DILUTED WITH N!IO KC1. 2.5 SEC. DROPS. Strength . . N / I o N/40 NIIGo dw/d logi . 0.077 0-0g.r 0.098 volts. From these results i t will be noted that the value of dw/d log i : ( I ) increases with dilution of the electrolyte; (2) is smaller when potassium is being liberated a t the cathode than when hydrogen is being liberated. Owing to the variation in the slope of these curves, no attempt is made here to measure the shift in the w/log i curves for solutions of different hydrogen ion concentrations. 3. In Table IV. are given the values of current a t the moment when the mercury drops separate from the capillary with increasing duration of the experiment, a t given applied E.M.F.'s.The solution studied was N/64 HCl + N/IO KC1 with 7 sec. drops, and the results for other solu- tions have been found to be similar in type.I4 STUDIES ON HYDROGEN 35. 42. --- 63 63 112 116 160 163 233 238 325 330 155 465 TABLE IV.-N/64 HCI + N/IO KCI. Current values, measured in units of 2-3 x IO-* amp., at given times in seconds after the application of the given E.M.F.’s. 49. 6 3 118 166 242 333 470 E.M.F. in m.v. I 166 1197 1213 1228 I244 I259 56. -- 63. 28. - 77. 63 167 250 340 480 I22 84. 91. --- 63 63 167 167 251 252 340 340 483 485 I22 I22 I I 53 83 I39 187 277 387 57 60 95102 I47 152 205 217 293 307 4=2 430 (53 167 215 337 472 I20 63 167 248 340 477 I22 63 167 247 340 475 I22 63 167 253 340 I 2 2 $87 98. 105. Secs. -1- 63 I22 167 253 340 459 Examination of these values shows them to vary logarithmically with time, the relation being of the form log (K - i) = k - t, i being the current, K and k constants.The fact that the current increases with time a t a given E.M.F. is surprising since this denotes that by this method the cathodic overpotential decreases with time. This is contrary to general experience with overpotential a t low current densities and to the results of Newbery This effect, which is a disadvantage of the dropping electrode for quantitative overpotential measurements, is possibly due to the creeping of the electrolyte into the capillary as a result of the pulsating effect of the mercury. From Table I17. it appears that the effect of time upon the value of dw/d log i is also considerable. This is illustrated in Table V., in which values of dw/d log i are shown for the first current values ob- served 6.6 seconds and for currents observed 2 minutes after the application of the corresponding E.M.F.and of Dunnill TABLE V. Solution . . . &t/d log i for first current dwld log i for last current N/I6HC1 $- NIIoKCI . 0.125 volt. 0.115 volt. N KC1 . . 0.078 ,, 0.060 ,, Hence the speed of the mechanical device used by Herasymenko would influence the value of dw/d log i found by him. 4. It was observed that whereas in acid solutions hydrogen bubbles were formed a t the cathode where the electrolysing current was greater than I x I O - ~ amp., in solutions of pure KCl or of KCl and KOH, none was formed. In all cases, the electrolyte was saturated by the passage of pure hydrogen for 30 minutes before each experiment.Details of two confirmatory experiments may be mentioned. N KC1 was elec- trolysed with a current of 2.6 x I O - ~ amp. (which is a much greater current than usually used in this work) for 45 minutes, mercury dropping at the rate of g drops per minute, and N/IO KCl with a current of 2-7 x I O - ~ amp. for 60 minutes, dropping being at the rate of 1 7 - 5 drops per minute. Despite the fact that the period of electrolysis was lengthy, in neither case was any cathodic hydrogen evolution noticed. value. value. J . Chem. SOC., 105, 2419, 1914 ; and 121, 7, 1922. 8 Ibzd., I 19, 1081, 1921.W. V. LLOYD I 5 Thus no conclusions regarding hydrogen overpotential in alkaline solution may be drawn from experiments with the dropping mercury electrode, the latter behaving simply as a potassium electrode. Summary.Experiments with the dropping mercury electrode were performed in order to elucidate the discrepancy between the value of d7rm/d log z given by Herasymenko (0.087 volt) and that given by Bowden (0.22 volt). It was found that w varies logarithmically with i for any solution provided that the rate of dropping be kept constant, that the current be measured at corresponding periods during the formation of a drop, and that it be measured after the same interval from the beginning of an experiment. The current was found to vary logarithmically with this latter interval, and hence i t was possible to vary the values of i and also of dw/d log z within considerable ranges by varying the rate of dropping. Variations of more than roo per cent were also found in the values of dw/d log i deter- mined for difierent solutions, but this result may very possibly be related to the former one, and it must be concluded that the mechanism of the dropping electrode is too complicated to render i t suitable for the study of hydrogen over-potential. In alkaline solution it was not found possible to obtain hydrogen gas from a dropping electrode. The latter can therefore give no information regarding hydrogen overpotential in alkaline solutions. The author wishes to express his thanks to Dr. Sand for his interest and advice during the course of this work. Sir John Cass Technical Institute, London, E.C. 3.

ISSN:0014-7672    

DOI:10.1039/TF9302600012

出版商:RSC    

年代:1930

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.

ISSN:0014-7672    

DOI:10.1039/TF9302600015

出版商:RSC    

年代:1930

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.

ISSN:0014-7672    

DOI:10.1039/TF9302600019

出版商:RSC    

年代:1930

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/TF9302600026

出版商:RSC    

年代:1930

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. 36 RA4DIATION FROM THE HYDROGEN-OXYGEN FLAME THE RADIATION FROM THE HYDROGEN-OXYGEN FLAME. BY W. E. GARNER AND K. TAWADA. (Received 7th October, 1929.) The radiation from flames consists in part of primary radiation from the newly-formed products of combustion, and in part of secondary radia- tion emitted by molecules which are a t a high temperature. Since the life of an excited molecule, such as those formed as a result of chemical change, is probably not much shorter than IO-'-IO-~ second, it is clear that the average molecule undergoes many collisions within its active life.I t may be deactivated during any one of these collisions, in which case i t emits no primary radiation or chemiluminescence. The quantity of primary radiation emitted will depend therefore on the probability of deactivation by collision. For the carbon monoxide-oxygen flames, the primary radiation or chemiluminescence is emitted during the process ( I ) co,' - co, + hv, and the deactivation by collision, by (2) CO,' + X CO, + X + thermal energy. In previous papers,l i t has been suggested that in the dry carbon monoxide flame, the second process is relatively slow compared with the first, especially when X is a molecule of oxygen, carbon monoxide or dioxide. In other words, a large proportion of the radiation from the dry flame of carbon monoxide and oxygen is primary in character.This is inferred from the fact that the presence of minute quantities of hydrogen or water in the carbon monoxide flame materially reduces the radiation emitted. It is concluded that the decreased emission is due to an in- creased rate of deactivation by collision by (z), where X represents a molecule of hydrogen or water. The concentrations of hydrogen employed, 0.005 to 0.1 per cent., are so low that the physical properties of the gaseous mixture are not materi- ally affected; thus, the thermal conductivity of the gas, its extinction 1 Garner and Johnson, Phil. Mag., 1927, iii, 97 ; J . Chem. SOC., 1328, 281 ; Garner and Roffey, J. Chem. Sot., 1929, 1133.W. E. GAKNER AND K. TAIVADA 37 coefficient, etc., are unlikely to be the direct cause of this effect.The decrease in the radiation emitted runs parallel with the effect of hydrogen on the speed of flame movement, discovered by Dixon. Wohl and Elbe,2 while admitting the possibility that the explanation of Garner and Johnson can be applied to the radiation from dry hydrogen and oxygen flames, throw doubt on its applicability to the flame of carbon monoxide, and suggest that the diminution of the radiation emitted is due to the shortening of the period of flame which occurs; they maintain that the radiation is thermal and that more radiation is emitted from the dry ,than from the wet flame because the high tem- peratures of flame are in existence for a longer time. This interpretation of the experimental results had occurred to us, but was considered not to apply, because any reduction in the velocity of the chemical change will lead to greater losses of heat to the walls during the process of com- bustion, and hence to lower flame temperatures.Since the radiation emitted varies as the fourth power of the temperature, and only directly as the time, it was considered that in the case of the slow moving flame, the factor of temperature was the more important and that the thermal radiation from the “ dry ’’ flame would be less than that from the “ wet ” flame. In the hydrogen-oxygen flame, the hydrogen itself or the water pro- duced in the flame may behave in the same way as i t does in the flame of carbon dioxide. The concentrations will be so high that it is not im- probable that deactivation according to (3) may be slow compared with deactivation by (4, (3) H,O’ H,O + hv.(4) H20’ + H,O (or HJ - 2H,O + kinetic energy, that is, the radiation from this flame may be almost entirely secondary in character. If the radiation from the hydrogen flame be thermal, and that from the carbon monoxide flame mainly chemiluminescence, then a comparison of their behaviour when inert gases are added or changes in pressure studied, would be helpful for the understanding of the whole problem of the nature of radiation from flame. The radiation from the hydrogen-oxygen flame has been studied by firing the gaseous mixture in a cylindrical bomb 2-5 crns. in diameter and 32 crns. long. The bomb was constructed in a similar manner t o that used previously, and could be fitted with either a fluorite or quartz window.The results obtained with a fluorite window were published in N a l ~ r e , ~ and those with a quartz window are given below. Effect of Drying.-The gases were slowly passed through a train of tubes containing phosphorus pentoxide, 1 5 0 crns. long. The bomb was dried by evacuation through a tube containing phosphorus pentoxide. A Hyvac and a mercury condensation pump were employed in series. After drying the gases, they could either be passed directly into the dried bomb, through a saturator containing water, or into a bomb saturated with water vapour. The radiation emitted from the flame was measured by the methods described previously. In the earlier experiments, the gases were fired by the ignition of iron wire, but this method of ignition was discarded because mixtures containing 60 per cent.or more of oxygen gave erratic results. The iron wire burnt to oxide more or less completely in such mixtures. Platinum wire was therefore used in all 2 Z . physik. Chem.. 1929, B5, 241. 1928, 122, 879.38 RADIATION FROM THE HYDROGEN-OXYGEN FLAME experiments quoted in this paper. This was fused by the application of a potential of 12 to 24 volts. The curve previously published in Nature for the radiation through a fluorite window is probably incorrect in the region of 60 to 80 per cent. of oxygen on account of the burning of the iron wire. The water produced in one explosion could be removed from the walls and window of the bomb within 60 minutes, and an increase in the time of pumping beyond this period had no effect on the radiation emitted.Neither could any change be observed if the bomb were filled several times with dry air and then evacuated after each admission. The results obtained with 3 0 2 + 2H2 are given below :- Time of pumping (mins.) . 60 I20 I20 120 1460* Deflection (cms.) . . . 38.1 37'2 36.4 38-4 38-6 The gas when saturated with water vapour at a temperature 3" below that of the room, gave similar results, viz., deflections of 41-0, 42'5, 39-5, 36.5, 37'7, 38.7 ems. I t was concluded from these results that water vapour had little They are of importance in view of the conclusions of Wohl and Elbe2 that the " dry " flame emits chemilu- minescence which is sup- pressed on saturation of the gaseous mixture with water.This deduction was made from the maximurn pressure reached in explosions of " dry " and " wet " hydrogen- oxygen mixtures in a 10-litre bomb. The gases were dried to an extent comparable with that in our experiments. In order to account for the lower maximum pressures given by the dry gas, they conclude that for the wet mixtures there is no appreciable loss of energy as radiation before the attainment of maximum pressure, but that there is a 3 to 7 per cent. loss of energy for the " dry " mixtures. In view of the above results, i t is doubtful if Wohl and Elbe's deduction is correct. It was thought advisable, however, to examine the effect of drying a mixture containing excess of hydrogen (3H2 + O,), since these authors have worked with such mixtures.A mixture saturated with water vapour gave radiation equivalent to 15-0 units, and drying for 240 minutes, 15.2 units, and for 1000 minutes, using the diffusion pump, 15.6 units. * I n this experiment the mercury condensation pump was used and the bomb filled with dry air repeatedly. effect on the emission from the hydrogen flame. 40 ii I6 i a 1D 50 FIG. I. bk=pcrunt.tc - 0 0W. E. GARNER AND K. TAWADA 39 There is only a slight increase on drying which is negligible compared with that claimed by Wohl and Elbe. In all subsequent experiments, the procedure was standardised. The pumps were applied for I hour and the " dry " gaseous mixture was used. Composition of Gases.-Variation in the composition of the gaseous mixture gave the results in Fig.I . Those for two pressures are given. The upper curve gives those carried out at an initial pressure of I atmo- sphere, and the lower those for atmospheric pressure. The maxima occurring a t 55 per cent. and 20 per cent. hydrogen were quite unexpected. A maximum a t 66 per cent. hydrogen was most probable for two reasons : ( I ) this is the composition for which the production of water has its maximum value J (2) it is the composition which gives the highest flame temperature. Bonhoeffer and Haber have demonstrated the existence of the hydroxyl radical in these flame^,^ and in discussing the results obtained with a fluorite window, i t was suggested that the maximum a t 55 per cent. might be due to radiation from the hydroxyl radi- cal (Nature, loc. cit.). The produc- tion of OH by the equation, H, + 0 2 - 20H, would attain its maximum value for 5 a mixture contain- ing 50 per cent.H,, and if this radical emitter of infra-red FIG. 2. radiation, the posi- tion of the maximum on the curve would be accounted for qualitatively. The spectrum of the radiation from the OH radical would be expected to differ in some respects from that emitted by water molecules, and the determination of the infra-red spectrum of the flames of mixtures con- taining 50 per cent. and 66 per cent. hydrogen might throw light on the above suggestion. The spectra for the flames of these mixtures are given in Fig. 2. On account of the small intensity of the radiation, a large slit width was used (see Fig. z ) , and i t was not possible to separate the maxima usually found in the spectra from the hydrogen flame.There are, however, no obvious differences between the qualities of the radia- tions from the two flames, that is, there is no direct evidence in favour of the view that the hydroxyl radical is the emitter of the radiation. The shift of the maximum in the curves of Fig. I is thus very probably due to the lower thermal conductivity of the mixtures containing excess oxygen (see below). Effect of Pressure.-The pressure-radiation curves for the mixtures 2H2 + O2 and 2H2 + 202 are given in Fig. 3. The curvature is note- worthy. The radiation from the flame decreases more rapidly than the were the principal WNe b& b)- 2. $hysik. Chem., 1928, 137, 263.40 RADIATION FROM THE HYDROGEN-OXYGEN FLAME pressure. Were the radiation of the nature of chemiluminescence, a curvature in the opposite direction would be FIG.3. rate of cooling: of the Droducts. expected, since at low pressures there should be relatively fewer deactivations by collision. Several attempts were ma.de to account for the form of the pressure curves by a mathe- matical treatment of various deactivation hypotheses, but all were unsuccessful. The cause of the pressure effect is very probably the increase in the aver- age mean free path which occurs on lowering the pres- sure. This increase favours a more rapid Effect of 6 e A d d i t h of Inert Gas.-It was therefore of interest to ascertain what would be the effect of lowering the flame temperature by the addition of inert gases. For additions of equal volumes of gas, the lowering of flame temperature will depend on the specific heat of the gas added.The results are summarised in Figs. 4 and 5 for the gaseous mixture, 2H2 + 02, to which argon, oxygen, nitrogen, helium, and hydrogen, respectively, are added. In Fig. 4, the effect of pressure is given and the form of the curves is similar to that of the curves in Fig. 3. The results on Fig. 5 are those for the hydrogen and oxygen mixtures a t 9 atmospheric pfessure. In- creases in radiation are observed on addition of the first three gases, and a de- crease for the last two. The threefold increase which occurs on the addition of argon is surprising if we consider solely the effect which this gas has on the 1 6 , flame temperature due to its ao 30 so 70 specific heat.If, however, prenuc of gu mL: br$ - its effect on the average FIG. 4. molecular velocity, or the conductivity for heat of the products, be taken into account, it will be seen that although the addition of argon will lower the flameW. E. GARNER AND K. TAWA4DA 41 Density of Products. temperature, it will also increase the duration of the high temperature of the flame. The radiation emitted will vary as T*, and directly as the duration of flame. Thus, the addition of an inert gas will exert two opposing effects on the radiation. I t would appear that the predominant effect in metal explosion vessels of the shape and dimensions used in this investigation is that due to changes in the conductivity of the heated products. This masks the anticipated effect due to the lowering of flame temperature.In agreement with this explanation, it will be observed that the effect of the gases is in the order of their densities, which is the same as that of their mean velocities and conductivities, as will be seen in Table I. The agreement between the intensity of the radiation and the densities and con- ductivities is only qualita- tive, for the speed of flame, and the specific heats, will also influence the duration of flame. The order is, how- ever, very different from that of inert gases on the speed of the hydrogen flame.5 Argon and helium have very similar effects on the speed of this flame. It is thus im- possible to account for the differences in the behaviour of the helium and argon mixtures in terms of the effect of the velocity of flame move- ment on the duration of flame.The thermal conductivity of the gases and its effect on the duration of flame is much the more important. In large spherical bombs this effect would probably be negligible, as Wohl and Elbe point out. TABLE I. Conductivity of Inert Gas, o°C. Mixture. Radiation. (Area.) 5-69 4-20 3'73 1 90 1-79 1-32 29 25 23 I 8 T I I 0 0.039 0.056 0'336 0'0 j7 - 0.400 When it is borne in mind that two very similar gases, argon and helium, produce such dissimilar effects on the radiation from the flame, it will be evident that a deactivation hypothesis similar to that put for- ward previously for the carbon monoxide flame is valueless for explain- ing the phenomena of the hydrogen flame. Both the pressure-radiation 6 Bone, Fraser, and Winter, Proc.Roy. SOC., 1927, I r4A, 402.42 RADIATION FROM ‘THE HYDROGEN-OXYGEN FLAME curves and the effect of inert gases indicate a thermal origin for the radiation from the flame. It is hoped that experiments of a similar character on the carbon monoxide flame will help to settle the question of the chemiluminescence from the carbon monoxide flame. Experimental, Preparation of Gases.-The hydrogen was prepared from pure zinc and pure sulphuric acid, and the gas was washed through alkaline per- manganate and water, and stored over water. It was dried as required over P,O,. The oxygen was prepared from potassium permanganate. The argon and helium were freed from other gases by passing through tubes containing (a) heated calcium oxide-magnesium, and (b) heated copper oxide, the process being repeated until the gases showed that hydrogen and nitrogen were absent when the purity of the gas was tested in a discharge tube.This method was suggested to us by Dr. M. W. Travers. Experimental Arrangement.-The gas holders A and B were used for storing dry hydrogen and oxygen respectively (Fig. 6 ) . The inert gas was stored in C. The gases were measured in D and passed through a lead tube into the holder F, from which they were led through tubes contain- ing P,O, into the bomb G, either directly or by way of a water saturator L. The initial and final pressures could be read on the manometer H, and the whole system could be evacuated by means of the mercury condensation pump I, and the Hyvac pump K.No rubber tubing was employed for connections between D and L. The radiation emitted was either (a) read visually, or ( b ) photographic- ally recorded by means of the apparatus described previously by GarnerW. E. GARNER AND K. TAWADA 43 The ratio of deflections by method (a) was identical with and Roffey.1 the ratio of areas by method was adopted. Inview of the possibility that very marked changes in speed might occur on the addition of inert gases, the experiments in Figs. 4 and 5 were carried out by the photographic method. Both fluorite and quartz windows were employed ; these needed special atten- tion and frequent polishing on account of the violence of explosion of some of the mixtures examined. The replacement of the iron wire used in firing by platinum wire, mentioned above, did not remove en- tirely the cause of the fluctu- ation in experimental values, especially in the region of large excess of oxygen (Fig.7). The cause of the fluctua- tions has not been traced, nor is the maximum which occurs a t about 20 per cent. understood. The mean values are given in Fig. I . (b) so that in general the visual method + . . H h p a c c n t r l r - FIG. 7. Effect 07 Addition -of Water, Nitric Oxide, etc.-Saturating various gaseous mixtures with water vapour, or changing the conditions of drying did not modify the values of the radiation. Gasmixture . H, + 0, H, + 20, zH, + 30, Addition of nitric oxide depressed the radiation slightly. Pressure NO, cms. 2-8 o 0.34 0 2'0 0'2 0.054 0 Deflection . 22-15 22.72 15-56 17-5 17-05 17-70 16-15 19.0 The results with nitric oxide are of interest in connection with the curious effect of this gas on the ignition temperature of hydrogen (Dixon).Experimental Results.-The results shown in the figures were all obtained by employing a quartz window. Fluorite windows were very liable to fracture, and so quartz was mainly employed. The ratio of the radiation emitted through fluorite to that emitted through quartz was about I : 1-45. In both cases, the windows were I cm. thick. The distance of the thermopile from the window was without effect on the ratios of the radiation from two flames with different percentage com- position.* * The fraction of the energy of chemical change which is emitted as radiation in the case of the 2H,+0, mixture a t I atmosphere pressure using a fluorite window is 2 per cent.This has been determined by comparison with a standard Hefner lamp, and employing the methods described by Johnson, Phil. Mag., 1028, v. 301.44 RADIATION FROM THE HYDROGEN-OXYGEN FLAME I Atmospher:. 2'0 2'3 4'2 0.6 0.3 0'1 0'0 0'0 0'1 0'0 The results can be read off from the figures with as great an accuracy as that of the results themselves, so that tables of data need not be given. Residual Pressures.-In measuring the pressures of the cooled pro- ducts of explosion, care was taken that the gases were saturated with moisture, even after expansion into the manometer. From these pres sures, the volume of the bomb, and the glass apparatus between i t and the manometer, the volume of the unburnt gas could be calculated. In many cases, this gas was analysed, and the analysis served as a check on the accuracy of admixture of the gases.Also, in some cases, the unburnt mixture was analysed. The combustion did not proceed to completion when excess of hydrogen was present, but in the case of the results a t one atmosphere pressure, combustion was complete in excess oxygen. The maximum unburnt gas occurred in the case of the most rapidly moving flame (66 per cent. HJ. The unburnt gas is given as a percentage of that theoretically possible in Table 11. 3 Atmosphere. 0.5 1'9 2.6 0'3 - 0.9 - 1'3 - 1'5 - 1'9 - 0'1 - 2'0 Gas Mixture. These figures refer to the results given in Fig. I. Tests were made for hydrogen peroxide and ozone in the liquid deposited after an explosion. Small quantities were shown to he present. Also, explosions were carried out in glass U tubes surrounded by liquid air. There was no difficulty in getting the flame to pass through explosive mixtures a t liquid air temperatures. The amount of hydrogen peroxide produced was not materially increased by this method even for the mixture (so2 + H2). Also, coating the interior of the tube with ice did not affect the production of H20,. Summary. The effect of composition, pressure, and the addition of inert gases on the radiation emitted from the flame of mixtures of hydrogen and oxygen has been measured in a cylindrical bomb, 2.5 cms. in diameter. The radiation is a t a maximum for the mixture containing 55 per cent. of hydrogen. The radiation decreases with reduction of pressure more rapidly than the pressure. Inert gases have an effect on the radiation emitted which is dependent on the density of the gas. Argon, oxygen, and nitrogen increase the radiation and hydrogen and helium decrease it. It is considered that the effects are due to changes in the duration of the high temperature of the flame. When two volumes of argon are added to three volumes of explosive mixture (2H2 + 02), there is a threefold increaseW. E. GARNER AND K. TAWADA 35 in the radiation emitted. emission of radiation. chemiluminescence of the “ dry ” flame is thus probably in error. that the radiation from this flame is thermal in character. Drying the gaseous mixture does not affect the Wohl and Elbe’s conclusion with regard to the The phenomena observed can best be accounted for on the assumption Our thanks are due to the Imperial Chemical Industries for 3 grant which has made possible the carrying out of this research. The University, Rrisfol.

ISSN:0014-7672    

DOI:10.1039/TF9302600036

出版商:RSC    

年代:1930

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. W. E. GARNER AND K. TAWADA 35 NOTE ON AN EXTENDED THEORY OF ACIDS AND BASES. BY T. M. LOWRY. Received 2 5 fh November, I 9 2 9. In a recent paper on “ Acid Catalysis in Hydrolytic Reactions,” Pro- fessor Bronsted and Mr. Wynne-Jones refer to “ the new theory of acids and bases ” which ‘‘ defines an acid as a substance which has a tendency to split OH protons and a base as a substance which tends to add on protons.” The origin of this conception is attributed to a paper bp Professor Bronsted under the title “ Einige Bemerkungen uber den Begriff der Sauren und Basen ” which was published in the summer of 1923.Since these definitions are now cited as a “new theory ” of acids and bases it is desirable to direct attention to an article on ‘‘ The Uniqueness of Hydrogen,” which appeared in Chemistry and Ikiz~rtt-y of January Igth, 1923, some months before Bronsted’s paper was received by the editor of the Receuil on May 4th of that year. In this article, the already familiar definition of an acid as a source of hydrogen ions was developed by attributing the acidity of aqueous acids to oxonium ions formed by a double decomposition with the solvent, ~ g . , C1H + H20 --2. C1 + OH, instead of to a mere dissociation into hydrogen ions C1H + C1 + H, and this was supplemented by a definition of a base as an “acceptor of hydrogen nuclei” instead of as a generator of hydroxyl ions.This conception of the relationship between acids and bases was also applied to explain the catalysis of the mutarotation of nitro-camphor by piperidine in benzene, under conditions which rendered untenable the traditional theory of catalysis by hydrogen and hydroxyl ions exclusively. Although, therefore, there was no idea at the time of claiming that the definition then given of acidity and basicity was either novel or original, it is clear that it had already led in 1923 to an extended theory of acid and basic catalysis, in which the catalytic effect of a base was attributed to the molecules as well as to the ions of the catalyst, just as Snethlage in 1923 had attributed catalytic activity to the molecules as well as to the hydrogen ions of an acid. The final paragraph in which these views were summarised is as follows : “ I t is commonly suggested that the alkalis or bases are as unique as the - + - *+ 1 Tram.Favadnjl Soc., 25. 59, 1929. Rcv. Tra-J. Chnr., 42, 7rS, 1923. - ~ Z . p l ~ ~ s i , ~ a l . Chenz.. 85, 311, 1913.46 REVIEWS OF BOOKS acids, and that the hydroxyl ion occupies just as peculiar a position as the hydrogen ion. This, however, is a narrow view, based on the fact that most of our chemical work is done in presence of water, if not actually in aqueous solutions. The real function of a base is that of an acceptor of hydrogen nuclei, and one of the simplest cases of neutralisation is the acceptance of a hydrogen ion by a molecule of ammonia, NHy + H + NH,.If the base is sufficiently strong it may not merely accept the free hydrogen nuclei which have been driven away from the molecules of an acid, but it may even steal them from compounds in which they are only weakly held, eg., from water, as in the action NH, + HOH == NH4 + OH. In this case the strength of the base is manifested by the liberation of hydroxyl ions, and can be measured by the proportion of these ions set free by each equivalent of the base. The hydroxyl ion is itself a strong base, since it is capable of accepting and retaining a very large proportion of the equivalent quantity of hydrogen ions.The combination of hydrogen with hydroxyl is, however, almost confined to aqueous solutions, whereas neutralisation by acceptance of a hydrogen nucleus may occur in any solvent in which hydrogen nuclei can be produced. I n the same way the most powerful catalyst for the iso- meric change of nitro-camphor is not a hydroxide, but a nitrogenous base, such as piperidine dissolved in benzene. This appears to set up isomeric change by providing an acceptor for the hydrogen nucleus, which can thus acquire a mobility which enables it to leave the nitro-camphor and return to a different position in the molecule.” In this passage the proton is still referred to as a hydrogen nucleus, although reference is made in the pre- ceding paragraph to the ionisation of an acid as involving “ the transfer of a proton from one octet to another.” I t may therefore be of value to recall the fact that the term ‘‘ proton ” was first put forward by Professor Ruther- ford, after consultation with his physical and chemical colleagues, in a paper read before Section A of the British Association at Cardiff in 1920, and that the word. was first published in Nature of November ~ r t h , 1920, under the heading ‘‘ Physics at the British Association.” + + + -

ISSN:0014-7672    

DOI:10.1039/TF9302600045

出版商:RSC    

年代:1930

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. 46 REVIEWS OF BOOKS REVIEWS OF BOOKS. Physics in Medical Radiology. By SIDNEY Russ D.Sc., F.Inst.P., L. H. CLARK, Ph.D., F.Inst.P., and B. D. H. WATTERS, M.Sc., A.1nst.P. Pp. xii + 234. (London : Chapman & Hall, Ltd., 1928. Price 12s. 6d.net.) If medicine were deprived of the services rendered to it to-day by physics there is probably no branch that would not suffer materially. In this connection it is interesting to notice that one of the most important steps towards a closer collaboration between physicists and medical men was taken originaily in this country about eighteen years ago through the provision both at the Middlesex Hospital and the Cancer Hospital of a department of physics. This plan has now been adopted by some other hospitals in England and extensively copied on the continent and in America. The establishment of a Diploma in Radiology and Electrotherapeutics in this country has also greatly assisted in developing the important part played by physics in medical Radiology. A book, therefore, which aims at covering most of the ground included in the special course of physics which medical men areREVIEWS OF BOOKS 47 now required to take in order to gain the Diploma, is very welcome at this juncture.It will be read with great interest by physicists who wish to know something of the extent to which their subject enters into these important courses, but it will naturally be studied more closely by those medical practitioners who desire to qualify themselves as medical radiologists. Incidentally, however, it may be pointed out that in the Preface “ physics ” is printed quite properly with a small “ p ” but ‘‘ electro-technics ” is given the distinction of a capital “ E.” The book itself begins with the statement of fundamental facts relating to static and current electricity. The notion of lines or tubes of force and the great part played in the progress of electrical science by such conceptions, so closely associated with the name of Faraday, is concisely explained.This first chapter ends with a reference to the electro-chemical actions taking place in ‘‘ accumu- lators ’’ and deals briefly with Faraday’s discovery of electro-magnetic induction. No research has played so vital a part in the development of the electrical industry throughout the world as this ; it has, in fact, made the modern X-ray installation possible. We next come to chapters which deal with the conduction of electricity through gases, and electro-magnetic waves, and thus we are led very appropri- ately to the consideration of the nature of emission from vacuum tubes. The authors then deal with the production and properties of X-rays and go on to describe the measurement of wave-length and the use of the spectiometer. The important question of the measurement of X-ray intensity, however, is treated with such brevity as to be of little practical use and neither the word “ Intensity” nor “ Measurement ” is indexed.Attention is next given to radioactivity and a concise account follows of the properties of those substances which spontaneously emit radiations. A short chapter is devoted to dosage in radium therapy and then comes a detailed account of photographic processes as applied to visible light and to X-rays. The rest of the book deals with ways and means and describes such things as electric motors, H.T.generators, measuring instruments, and so forth. Two important appendices are added, one giving the third revised report of the X-Ray and Radium Protection Committee and the other an account of (‘ A Hospital Radium Service.” All interested in the progress of radiology must feel indebted to the authors for having brought together such a large amount of valuable information. Industrial Carbon. By C. L. MANTELL, Ph.I). (Industrial Chemical Mono- graph. London: Chapman & Hall, Ltd., 1928. Pp. ix and 410. Price 2 IS. net.) In this book an attempt has been made to compile a description of the various uses of carbon, other than as fuel. There are zg chapters each dealing with a separate use, but many are little more than long paragraphs.The main part of the book is devoted to Electrodes (about roo pages) and to Adsorbent Charcoals (4 chapters, about 120 pages), whilst there are assorted chapters on diamonds, graphite (with separate chapters for its various uses), pigments, etc. If the reader has the curiosity to wish to know how many ways there are in which carbon is used he will find the information in this book. But will he be willing to pay a guinea to satisfy this craving? If, on the other hand, he really wants to know something about, say, electrodes would he go to a book of SO catholic a nature and title ; it is, at least, doubtful,48 REVIEM5 OF HOOKS Hydrogen Ions. By HUBERT S . BRITTON. Monographs on Applied Chemistry. Pp. xiv + 5 I 5 . (Chapman & Hall, 1929. Price 25s. net.) The determination of hydrogen ion concentration has assumed an importance in pure and applied chemistry which makes it desirable to have special treatises on the subject, and although one well-known work has already gone through several editions there was room for others dealing with a wider range of subjects.Dr. Britton’s book thus fills a place in this literature. It deals with the various electrometric and colorimetric methods, gives a general account of the importance of hydrogen ion concentration in volumetric and gravimetric analysis, including electrometric titrations, and then discusses the applications in industrial processes, including tanning, brewing, and soil fertility. The theory is particularly clear, and this part of the book will be welcomed by those chemists who have long been engaged in work of a different type, and who find it necessary to use and understand this newer adjunct to the analytical laboratory.Every point is carefully explained and the formulz deduced with a minimum of mathematical machinery. The results are clearly stated and can be understood and applied without the necessity of following the deductions. The treatment is confined to the use of concentrations, not activities. The quinhydrone of glass electrodes are included, and full directions are given for the setting up of all electrodes and for preparing the solutions used. The use of alizarine red for the titration of solutions containing nitrites might have been mentioned. There seems to be a slight confusion on page 2 50 between exponents and logarithms (which is obvious), and the punctuation on the bottom of page 243 is rather unusual.Dr. Britton’s book is one which can be recommended both to students and to chemists who have occasion to make use of these methods, and when the large amount of valuable information (including references to literature) which i t contains are considered the price is reasonable. The printing and illustration are excellent. J. R. P. Molecular Magnetism. By W. PEDDIE, D.Sc., F.R.S.E. (London : The author states that one of his aims is to provide an introductory textbook to the larger treatises on magnetism which have recently appeared, and although he gives a very clear statement of many of the fundamental conceptions of magnetism, the reviewer considers that this book would be more accurately described as a short memoir on the theory of magnetic crystals. Very little attention is paid to the more modern developments in magnetism, and the final chapter of some half a dozen pages on the quantum and magneton theories can scarcely be regarded as an adequate introduction to modern work, particularly when the experiments of Garlach and Stern are dismissed in a very short paragraph. The reviewer feels that students will find difficulty with the author’s presenta- tion of the experimental work on the gyromagnetic anomaly. No reference is made to the original papers on the subject, and the impression is conveyed that the gyromagnetic ratio for strongly paramagnetic substances is one half the theoretical value. Now, up to the present time, the published researches have dealt entirely with ferromagnetic substances ; although the reviewer is aware that important measurements on paramagnetic substances are in hand, their results are not yet available. Edward Arnold & Co., 1929. Price 10s. net.) L. F. B.

ISSN:0014-7672    

DOI:10.1039/TF9302600046

出版商:RSC    

年代:1930

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.

ISSN:0014-7672    

DOI:10.1039/TF9302600049

出版商:RSC    

年代:1930

数据来源: RSC