2582 SHRODER ANn ACtlEE: CATALYSIS. PART XVIII.CCXL.-Catalysis. Part X V l II.* The &actions ofBoth the h i s and the Molecules of Acids,Buses ccnd Salts: The Reactions of Alkyl Haloidswith Phenoxides and Bthoxides.By JOHN HANSTON SHRODER and SOLOMON FARLEY ACREE.THE two recent papers by Segaller (T., 1913, 103, 1154, 1421) cnthe action of alkyl haloids on sodium phenoxide show that thereaction-velocity increases with dilution, the formulaK,=K,+alog V ,used by Hecht, Conrad, and Briickner (Zeitsch. physikal. Chem.,1890, 5, 289), applying equally well t’o Segaller’s results. Eversince the brilliant work of Arrhenius on the ionic theory, and ofOstwald on the relation between the ionisation of acids and theiractivity in ester catalysis, inversion of sucrose and hydrolysis ofacetamide, chemists generally, Kahlenberg ( J .Physical Chem.,1901, 5, 339; 1902, 6, 1) especially, Michael (Amer. Chem. J.,1910, 43, 322) and Armstrong being notable exceptions, havebelieved that only ions enter appreciably into chemical transforma-tions. Even the known “ deviations from the ionic reactions,”especially those produced by added salts, were thought t o be dueto a change in the ionic reaction by the salts themselves. As itwas pure chance that Arrhenius and Ostwald worked with reactionsin which ions are chiefly concerned, and as the “deviation fromthe ionic reaction ” or “ salt catalysis ” observed by them couldbe partly or wholly due t o the reactions of the non-ionised electro-lytes, the workers in this laboratory have since 1905 been usingthe theory that both the ions and molecules of acids, bases andsalts, must in all cases be examined f o r activity. Johnson andAcree in 1907 (Amer.Chem. J . , 37, 410; 38, 258) brought outthis idea clearly f o r salts, and in 1908 Shadinger and Acree wrote :“ We are studying the problem whether acids, bases and salts enterinto these reactions through their ions o r molecules, or both.”Besides the discussion of “salt catalysis” (ibid., 1908, 39, 230),we gave the equation (ibid., p. 228) dxldt =KtrnllSa(A -z>2 for thereactions of the ions, as Arrhenius, Ostwald, and all others sincethem have done, and then gave (ibid., p. 228) the equationiEx/dt = X’tr:L,,s (1 - a ) ( A - z)2 for the activity of the “ undissociatedacid, base o r salt,” this idea and equation being the first newcontribution t o the theory of chemical reactions and the cause of* For references t o the earlier papex see dmer.Chem. J., 1913, 49, 474SHRODER AND ACREE: CATALYSIS. PART XVIII. 2583the ‘( deviations from the ionic reactions I’ or “ salt catalysis ” sinceArrhenius’ brilliant work in 1885. Before the American ChemicalSociety in Baltimore, in December, 1908 (Scieme, 30, 624), oneof us stated that: (‘We see, then, that the question whether theanion or cation (simple or complex) or the molecular form of agiven acid, base, salt or other neutral substance, is the chief con-stituent transformed directdy into the end products dependsentirely upon the relative magnitudes of the various constants, andtherefore varies widely in the different problems.” Our work(,4mer.Chem. J . , 1912, 48, 352; 1913, 49, 116, 127, 345, 369, 474,and earlier papers) has now shown that this new idea of theactivity of non-ionised electxolytes is fully as important forchemical reactions as the idea that ions are active. To expressreaction-velocities completely, we must use the equationK , =‘[liia + K ?n (1 - a> ][I + (f>c.&1tI.The second term on the right side of the equation represents afactor for “salt catalysis,” and the first term gives the activity ofthe ions and molecules in normal solutions having the ionisationa and the velocity X,. This theory has been found t o hold inabout thirty reactions studied by us in concent’rated solutions( N / l t o N/32), as well as in ideal solutions ( N / 3 2 t o N/2048), thework involving the three most important classes of chemicalchanges, namely, metathesis, pure catalysis and intramolecularrearrangement.By this theory we have been able to reinterpretthe older work of Arrhenius, Ostwald, Conrad and his co-workers,Koelichen, Tubandt, Stieglitz, Bredig, Goldschmidt, Holmberg,Senter, Walker, van Dam, Blanksma and Segaller as reactions ofboth ions and molecules, instead of ions alone. The theory has,furthermore, now been accepted and used by Arrhenius (Taylorand Arrhenius, Medd. X. Vetenskapakad. Nobelinst., 1913, 2,Nos. 34, 35, 37), Stieglitz ( J . Amer. Chem. Soc., 1912, 34, 1687,1688, 1689, 1690, 1694; 1913, 35, 1774), Dawson (T., 1913, 103,2135 ; this vol., p.1093), Goldsclimidt (Zeitsch. Elektrochezm., 1909,15, 6 ; Zeitsck. physikal. Chcm., 1910, 70, 627), Bredig (Zeitsch.Elektrochem., 1912, 18, 535, 543 ; Zeitsch. physikal. Chem.,1913, 85, 129, 170, 211), IIolmberg (Zeitsch. physikal. Chem.,1913, 84, 451, 468; 469), Biddle ( J . Amer. Chem. SOC., 1914, 36,99, and earlier papers), Kilpi (Zeitsch. plqsikal. Chem., 1913, 86,427, 644), and Worley (Phil. Mug., 1914, ‘[vi], 27, 459), and bidsfair t’o become generally useful in all reactions involvingelectrolytes.Segaller ‘studied the reactions of N / 2-sodium phenoxide with anumber of different alkyl haloids a t 42‘5O in order to measuretheir relative chemical activities. Fortunately, he investigated the8 F 2584 SHEZODER AND ACREE: CATALYSIS.PART XVIII.action of Ii-propyl iodide OIL varying concentrations of sodiumphenoxide, and it is this work that interests us a t present, as i textends our series of investigations with methyl and ethyl iodidesa t 2 5 O and 3 5 O . Lack of time alone is all that has prevented usfrom using all the other alkyl haloids in our work on the phen-oxides, ethoxides, and urazoles. We have now extrapolatedSegaller’s data to obtain the reaction-velocities for solutions exactlyN / 2 , N/4, i V / l O , and N / 2 0 , and have found by the use of ourequation, K , = Kia + Em(1 - a), that his data harmonise excellentlywith ours and with our theory, both the phenoxide ions and thenon-ionised sodium phenoxidc seeming to react with )+propyliodide, as follows :C,H71 + OC6H, -+- C,H7*O*C,H, + I ;C,H,I + Na0*C6H5 + C,H,*O*C,H, + NaI.The following tables show the values of K’, and Arm obtained byus from our own work on methyl and ethyl iodides and sodium,potassium, and lithium phenoxidea at1 2 5 O and 3 5 O , and fromSegaller’s work at 42’5O.Because of larger experimental errors,the values of Ki do not agree as well a t 3 5 O as a t 25O. The valuesof a used by us in recalculating Segaller’s data were obtained byextrapolation of H. C. Robertson’s data f o r sodium phenoxide a tOo, 2 5 O , and 3 5 O . It is seen that the ratio Ki/Iim for both methyliodide and ethyl iodide and sodium phenoxide is from 5 to 6 a t 2 5 Oand 6 to 7 a t 3 5 O , whilst f o r propyl iodide it is about 17 a t 4 2 * 5 O ,and the reaction is almost purely ionic in solutions more dilutethan N/50. The value for Iii for the phenoxide ion and methyliodide is about five times as large a t 2 5 O and 3 5 O as that forethyl iodide, which in turn is about three times the value for Kifound for the phenoxide ion and propyl iodide a t 42’5O.Temperature, 25O.Sodium phenoxide and methyl iodide .. .Sodium phenoxide and ethyl iodidePotassium ,, y 7 Y9 3 , 0 . . Lithium , Y ?, Y , 7, .*.Potassium ,, Y ? 1 , Y Y * * .Lith4um ,, 93 Y , 9 9...Temperature, 3 5 O .Sodium phenoxide and methyl iodide . . .Potassium 7 y 7 ) 7 7 Sodium phenoxide and ethyl iod%e ...Potassium ,, 3, 2 , Y7 Lithium ), Y 9 2 9 7 7 *.....Temper a tare, 4 2 * 5 O .Sodium phenoxide and propyl iodide ...Ki.0.02820.02830.02870.005510.005 180.005340.09090.10360.01830.01970.01740.0128K,.0.004770.003700.003930.0009870~0010110.0009 100.013 100.009830.003 2 30-002700.003190*00075SHRODER AND ACREE: CATALYSIS.PART XVIII. 2585Our chief interest in Segaller’s work and that of Hecht, Conrad,and Bruckner lies in the fact that the change in K , with dilutionfollows the equation K,=K1+a log V , as written by Hecht,Conrad, and Briickner.KIN - Ii, =a log ( V f / V ) ,in which K f , and K , represent V / K v , and V K v , the reaction-velocities for the concent’rations 1/V’ and l l V , as used in ourformer papers. This equation is purely empirical, has never beengiven any scientific foundation, and it does not involve the chang-ing ionisation of the ethoxide, or phenoxide, because Hecht,Conrad, and Briickner did not consider the possibility of theionisation of the sodium etlioxide or phenoside, but spoke of allthese substances as non-electrolytes, or “ nichtleitende Korper.”We have therefore interested ourselves in determining why thissimple equation holds so excellently, as it, undoubtedly does, forall the work of Hecht, Conrad, and Briickner, Segaller, and forthat part of ours to which we have applied it.When we write Conrad’s equation as (1) ZI, - K , =a log (1’1 / Ti),and two of our simultaneous equations as (2) K , = Kia + K,(I - a )and (3) KIN= Kia/+ K,(I - a/), and subtract (2) from (3), we get(4) K / , - K , = ( K i - K,) (a1 - a ) .By comparing equations (2) and(4) we get (5) KIN - K , :=u log ( V / / V ) = ( K i - Km)(u’ - a), andA more general form isn log (Vl/ V ) of Conrad’s equation (I) has a scientific basis, there-fore, only if equation (6) actually gives “constants” f o r n. Wehave recalculated Segaller’s work, and Dr. W. A. Taylor has thatof Hecht,, Conrad, and Briickner, and we have also applied theseequations to much of our own work; we find that equations (6)and (7) hold excellently within the experimental errors. O€course, the central point hinges on the validity of the relation#= K, an empirical equat’ion t,liat holds very well in the a - alog ( ul/ P)mire concentrated solutions of a number of electrolytes t o whichwe have! applied it, whether the electrolyte obeys the Ostwalddilution law or is too ‘‘ strong ” to do so.This equation cannothold for all concentrations, because the ratio V1/V keeps onincreasing after complete ionisation is reached, whereas a/ - a thenremains constant.. We are investigating all these relations fully,and extended reports on the work of Segaller, and of Hecht,Conrad, and Briickner, will soon be published by Dr. J. H. Shroderand Dr. W. A. Taylor.It is seen in tables VI of both sections of the experimental por-tion that both equations (6) and (7) give very good constants fo2586 SHRODEE AND ACREE: CATALYSIS. PART XVIII.a, the two values, 0.00265 and 0*00269, for sodium phenoxide andpropyl iodide a t 42’5O agreeing better than the values 0.0247 and0.02594 for sodium ethoxide and methyl iodide a t 24O.It is seenin tables VII of both sections that the values for (I K , calculated ”agree well with those for (( XN found.”It is thus seen that the empirical relationK‘, - KN = a log ( v// v)used by Hecht, Conrad, and Briickner, and by Segaller, and therelation KIN= ITN observed by Bredig (Zeitsch. iTleklrochem., 1904,10, 582),, Tubandt (Annalen, 1905, 339, 41 ; 1907, 354, 259;1910, 377, 284), Steger (Rec. trau. chim., 1899, 18, 13, 41), andby McCombie and Scarborough (this vol., p. 1304), and Myers andAcree (Amer. Chem. J., 1912, 48, 358; 1913, 49, 144, 3671, andthe salt-catalysis equation, K , = X , a + K,a2, or its equivalent, usedby Arrhenius, Spohr, Euler, Stlieglitz and others, are all specialcases that can be converted into our general equationinvolving the reactions of both the ions and the non-ionised formsof acids, bases, and salts.K , =’[&a + Km( 1 - 4[1+ (f)Q,,,,],Imteraction of Sodium Phenoxide and Prop$ Iodide at 42.5O.TABLE I,K, Found for Sodium Phenoxide and Propyl Iodide at 42’5O.Concentrationof sodiumphenoxide.V .K,. K , average.2 0.002800.002930.003050.00309 0.002974 0.003690.00371 0.00370Concentrationof sodiumphenoxide.V . K,. K , average.10 0.0048020 0.005520.00475 0.004780.00571 0,00562TABLE 11.Ionisation of Sodium Phenoxide at 42.5’.V . a. l-a.2 0.1826 0.81744 0.2400 0.760010 0.3265 0.673520 0.4065 0.593SHRODER AND ACREE: CATALYSIS. PART XVIII.2587TABLE 111.Ki and I<, Found for Sodium Phenoxide and Propyl Iodidea,t 42*5O.Ki.v=2 : v = 4 0.0 13 37v=2 : v=10 0.01325v = 2 : v=20 0.01264 v=4 : v=10 0.0 13 19v=4: v=20 0.0 1246v=10: v=20 0.01185Km.0.0006480.0006730~0008090.0007040.0009320*001364*Average 0.01280* This value was omitted.0.000753TABLE IV.K, Calculated and Found for Sodium Yhenoxide and PropylIodide at 42’5O.V. K,. K, calculated. Error, per cent.2 0.00297 0.00295 + 0.74 0.00370 0.00364 + 1.610 0.00478 0.00469 + 1.920 0.00562 0.00565 - 0.5. TABLE V.Per Cent. of Reaction Due to Ions and to Molecules.Concentration ofsodium phenoxide Per cent. of reaction Per cent. of reactionV. due to a K;.due to (1 -a)&.2 79-14 20.864 84-40 15-6010 89-10 10.9020 92.09 7.91TABLE VI.a ” Found for Sodium Phenoxide and Prom1 Iodide at 42.5O.a=- K’, - K , (Ki-Km) ( ~ ’ - a ) .log( V‘/V)’ a = 1% ( V’/ V )v = 2 : v = 4 0.002425 0.002297v = 2 : v=10 0.002589 0.0024801.‘-2: TTZT20 0*002650 0.002698v-4: v-10 O.0027 13 0.008G18J’Z4 : 1’-20 0.002746 0.002870T’710 : v=20 0.002789 0.003205Average 0.00265 0.00262588 SHRODER AND ACREE: CATALYSIS. PART XVIIT.sodium ethoxide K,.1 0.055122 0.062766 0.07 18210 0.07950sodium ethoxide Kh .20 0.0869640 0.0944880 0.1022v.TI= 1 : v = 2 v = 1 : v= 5 v = l : V = l OV= 1 : v = 2 0V= 1 : V=4OV= 1: V=80 v = 2 : v = 5V= 2 : v=10 v = 2 : V=20V== 2 : V=40 v = 2 : V=80V= 5 : V=10V= 5 : V=20V= 5 : V=40V= 5 : V=80V=10: v=20V=10: V=40v=10 : V=80V=2O: V=40V=20: V=80T7=40 : V-801 0.1470 0.85302 0.2346 0.76545 0.3336 0.666510 0.4170 0.5830Average20 0.5075 0.492540 0.6040 0-396080 0.7030 0,2970Ki.0.12940,12150.13120.13040-12840.12740-13280.13300- 13060.12810.12730.13310.12970.12760.12670.12750.12620.12580.12530.12550- 12560.1287-__K*.0.042300.04 1940.041840.042 120.042440.042640.041260.041220.04 1940.042600.042960.041140.042800.043860.044340.045100.046080,046300.047400.047260.04 7 000.0435SHRODER AND AGREE: CATALYSIS.PART XVIII. 2589TABLE IVK, Calculated and Fozcnd for Sodium Ethoxide and MethylIodide at 24O.K,.Error in v. K,. calculated. per cent.1 0.05512 0.05605 -1.682 0.06276 0.06352 -1.215 0.07182 0.07194 -0.1610 0.07950 0.07905 +0*57K,. Error inV . K,. calculated. percent.20 0.08696 0-08676 +0*2380 0.1022 0.1034 -1.1740 0.09448 0.09498 -0.52TABLE V.Per Cent. of Bectctiorh Due t o Ions and to Molecules.Concentra-tion of (sodiumethoxide.12510Per cent.If reactiondue toaKi.33.7547.5369-6667.89Per cent.of reactiondue to(1 - a)Kn.66.2552-4740-3432.11Concentra- Per cent. Per cent!tionof of reaction of reactionsodium due to due toethoxide. &Ki. (1 - a)K,.20 75-28 24.7240 81.84 18-1680 87.51 12-49TABLE VI.( ( a ’ 7 Found for Sodi~unz Ethoxide and Methyl Iodide a t 24’.a =v = 1 : V= 2 v = 1: V= 5V= 1 : V=lO v = 1 : V=20V= 1 : V=40V= 1 : V=80V= 2 : v= 5 v= 2 : V=10 v = 2 : V=20T i = 2 : V=40V= 2 : V=80 v= 5 : V=lO v= 5 : V=20V= 5 : V=40V= 5 : V=80V=10: V=20V=lO: V=40 “ = l o : v=soV=20: V=40V=20: V=80V=40: V=80K’, - K ,l O g ( V ) ‘ a0.025380.023880.024380.024470.024560.024740.022760.023930.024200.024380.024310.0255 10.025 150.025090.045230.024780.024880.025 130.024980-025310.025640.024780.0227 10.022990.023590.028510.029210.021160.022210.027290.028370.029230.023280.024610.025500.026220.025600.029440.026970-027300- 0 2 7 6 80.02800Average 0.02470 0.02592590 SHRODEK AND ACREE: CATALYSIS.PART xvm.TABLE VII.KN Pound, K, Calculated fobtained by using a ” in the EquationK‘N=K, + a log (V/V)], and Percentage Error.K NV , found.1 0.055122 0.0627 65 0.071820.0795020 lo 0.0869640 0.0944880 0.10220K , calculatedfora= 0.02470.0.054580.06 1990.071820.079480.086690.094120.10 159Error,per cent.+ 0.99 + 1-24 + 0.00 + 0.03f0.31 + 0.36 + 0-59K , calculatedfora = 0.02594.0.053720.061500.071820.079630.087430.095240.10305Error,per cent. + 2-60 + 2.010.00-0.16- 0.54- 0.79- 0.81Conclusions.(1) It has been shown that the work of Hecht:, Conrad, andBriickner on the interaction of methyl iodide and sodium ethoxidea t 24O, and that of Segaller on t4he inbradion of n-propyl iodideand sodium phenoxide a t 42*5O, harmonises with our own workalong these lines. Their data give constants for X i and K , whensubstituted in the equation KN =Ria + K,(1- a), and furnishexcellent evidence that both the ethoxide and phenoxide anions, aswell as the non-ionised sodium ethoxide and sodium phenoxidemolecules, react with the alkyl haloids. The values Ri=0.1287and Rm=O.O4354 are found for methyl iodide and sodium ethoxideat 24O, whereas Ki=0*0128 and R,=0*000753 are found forsodium phenoxide and propyl iodide a t 42.5O.(2) Hecht, Conrad, and Bruckner, and Segaller, found that thereaction-velocitim can be expressed accurately by the equationK’N=KN + a log (TI/ V ) , an equation which does not lake into con-sideration the changing values of the ionisation of the ethoxidesand phenoxides. We have found that this equation harmoniseswith our theory and the equation KN = Kia + K,(l - a), becauseof the fact that the changes in volume, ionisation, and reaction-velocity correspond closely with t-he equationsWe are indebted to the Carnegie Institution of Washington foraid in this work.JOHNS HOPKINS UNIVERSITY,BALTIMORE, MD