Sept., 1962
1749
XOTES
water, methanol, ethanol, benzene, acetone, and chloroform at room temperature, using marine barometer tubing supplied by the Corning Glass Co, The bore radius \vas determined by capillary rise of water to be 2.70 X cm., and was checked by direct examination with a calibrated microscope, which gave r = 2.71 X lom3cm. With water at 27.4', p = 0.996 gJcrn.3, hF was 54.2 em., an.d ti/, was found to be 98.7 and 98.9 see. in two separate runs.6 The viscosity calculated from eq. 4 is 17 = (0.647)(2.70 X 10-3)2(0.99G)(980)(98.8)/ 54.2 = 8.44 X 10-3 poise = 0.844 cp. This value compares quite favorably with the value 0.846 cp. obtained by interpolat'ion of recorded viscosity data7for water a t various temperatures. I n conclusion it may be pointed out that the present work serves as a coilfirmatlionof the validity of Washburn's eqmtion, as well as providing a new rapid method for simply and accurately determining %heviscosity of a liquid, using samples considerably smaller tha.n heretofore possible with other methods. (6) If t,he same capillary tube is to be used again for a second liquid, i t is, of course, necessary to clean the tube carefully with cleaning solution, followed by a few rinsings with distilled water and then acetone. Finally, the tube must be dried thoroughly. When the tube is not in use, i t should be covered a t hoth ends to prevent the smallest traces of dust from entering. If reproducible half-times cannot be obtained, the capillary is not clean, and in some cases t.he only r e m i d r is to take a new section of capillary tubing. (7) Handbook of Chemiatry and Dhysics, 41st E d . , Chemical Rubber Publ. Co., Cleveland, Ohio, 1960, p. 2181.
Experimental DMD-BDS was prepared from DMDClz, made by Houdry, and Eastman HzBDS. After converting the DMDCh t o the sulfate by addition of silver sulfate, the DMDSO4was precipitated from the aqueous solution by evaporation and addition of ethanol, and was recrystallized from methanol containing a little water. These salts are very soluble in water but nearly insoluble in most' other solvents. I n order to remove sulfuric acid from H2BDS, it was converted to the barium salt in aqueous solution by barium hydroxide, and the BaBDS (12.6 g./15 ml.) was recrystallized from water. The DMDS04 was titrated in aqueous solution t o a nephelometric end-point with BaBDS. After filtering off the barium sulfate, the DMD-BDS was precipitated by addition of ethanol. The salt was recrystallized twice from methanol-water, washed with 7: 1 methanolwater, and dried t o constant weight a t 30 p and 138'. Water probably still was present in the salt, but a higher temperature was not risked. Wet test.s for barium and silver were negative and the salt was neutral. For the preparation of DMD-BPDS, the DMDC12 was recrvstallized by dissolving 5 E. in 10 ml. of hot methanol, then adding an kqual amount 4 ethanol, and evaporating to about one fourth the volume. The salt then was ronverted to the hydroxide by silver oxide. Eastman p,p-diphenyldisulfonic acid was converted t o the potaesium salt, which was recrystallized twice from water. The acid then was formed in aqueous solution by passing a solution of the potassium salt through a Duolite C-3 cation exchanger. The acid was titrated to a methyl orange end-point with DMD(OH)2. After reducing the volume of solution, salt was precipitated by the addition of methanol. The salt was dried for two days a t 78" and 30 p . The methods of measurement have been described previously6; the cell used in these measurements had a constant of 1.0109.
Results The data for the conductance of DMD-BDS and DMD-BPDS are given in Table I. TABLR I
CONDUCTANCE OF 2-2 ELECTROLYTES WITH MULTIPLE CHARGE SITES BY JOHN E . LIND,JR.,'A K D
RAYMOND
CONDUCTANCE O F N,N-DIMETHYLTRIETHYLA~IMOFIUM SALTS
IN WATER AT
M. FVoSS
Contrzbutzon N o . 1698 from the Sterlzng Chemistry Labolatory of Yale Unzverszty, New Haven, Connectzcut Eeceived Aprzl 18, 196%
The conductance theory of FLIOSS and Onsager2 has been applied extensively to 1-1 electrolytes, but there has been little examination of higher symmetrical charge types because the inweased electrostatic fields redulce the range of applicability of the theory. Atkinson3-5 and co-workers have investigated a number of metal salts of m-benzenedisulfonic acid (H2BDS)and p,p-biphenyldisulfoiic acid (H2BPDS). However, no 2-2 salts have been investigated whlere the anions and cations are both large and of comparable size. For such salts the electrostatic interactions at contact are smaller and thus they better approximate the theoretical model. The purpose of this note is to present conductance data a t 25' in water for two such salts: the K,K-dimethyltriet hylenediammon ium (DAID) salts of BDS and BPDS. DMD is the dimethyl quaternized ion of 1,4-diaza-bicyclo [2.2.2]octane with the structure MeN+(CH2CH2),Y+Ne. (1) Du Pont Postdoctoral Research Fellow, 1960-1962 (2) R. >I. Fuoss and F. Accascina, "Electrolj tic Conductance," Interscience Publishers, Inc., New York, N. P., 1959. (3) G. A4tk~nson, &! Yokoi, I. and C Jd Hallada, J . A m Chem Sac., 83, 1670 (1961). (4) C. J. Hallada and C.Atkxnsoa, dbzd., 83, 3759 (1961). (6) C . J, Hallada and 6. Atkinaad, ibid., 83, 4367 (tqfit).
104~
DMD-BD8 A
25" DMD-BPDS
lOaAA
27.161 102.53 -2 20.754 105.83 3 15.529 109.22 1 10.996 112.94 -4 5.657 119.09 1 c/m = 0.99707 - 0.32 m
A
104,
lO*Ah
20.747 101.14 -1 16.821 103.07 $2 12.472 105.62 0 8 065 108.98 -2 +I 4 143 113.22 c/m = 0.99707 - 0.29 m
They mere analyzed by the Fuoss-Onsager equation A
=
+
A, - S ( C ~ ) "Ecy ~ log cy
+ Jcy +
Jz(cy)'''
- KACyf2A
The analysis was made on an IBM 709 computer with Kay's' program in Fortran which was modified by the addition of the cs/z term in the conductance equation. h second modification of the program was the addition of the condition that, if the association constant, K A , becomes negative, the fraction of free ions is set equal to unity. This change was made because it appears that a small term in J was neglected which is by this analysis added as a small negative component to K A . I n Table I, AA is the difference between the observed conductance and the value computed from the (6) J. E. Lind, Jr., and R. M.Fuoss, J . P h p . Chem., 66, 999 (1961). (7) R. L. Kay, J . Am. Chem. Sac., 83, 2099 (1960). Jn order t o adapt the program for 1-1 salts to data for 2-2 salts, one simply replaces the dielectric conntant 0 hs 0/4 and th6 vimmitv 7 by q / 2 ,
1730
T'ol, 06
KOTES
Fuoss-Onsager equation, The dielectric constant and viscosity of mater used in ihe computation were 78.54 and 0.008903 poise, respectively. The density of both salts is about 1.43. The maximum correction for solvent conductance was 1%. The results of the analysis are given in Table I1 where AC = limiting conductance, UJ = ion size parameter from J-terms in the equation, K A = association constant for the formation of ion pairs, and U A = standard deviation in A-units of the data points from the equation.
TIIE HEAT OB FORR.IATION OF GASEOUS
METHYL NITRITE' BY JAMES D. RAYAXD A. ARSOLDCERSIION % h o d of C l r r i r i r d i g , CIIroioiu Instilute of 'I'eLhnoloyy, ilfiuiitu 13 6'eoi
yzo
Itrcezted .Julg ii, 19Cl
Calculations which have been made recently by Gray and Pratt2 indicate that the value for tho heat of formation of methyl nitrite calculated from the equilibrium study of Leermakers and Ramsperger3 is somewhat in error. Although Gray TABLE I1 a r d Pratt2 quote unpublished data of Baldrey, DERIVEDCONSTANTS Lotsgesell, and Style as evidence for a revised Salt Ao dJ KA ah value for the heat of formation of methyl nitrite. DMD-BDS 134.35 f 0.15 4.30 f 0.13 40 f 5 0 04 this value was obtained from solution calorimetry DMD-BPDS 124.08 z!z 0 09 4.41 f .14 -5 z!z 4 0.03 ar,d depends ultimately on a small difference beThe association constant of the DMD-BDS is tween two large numbers. Geiseler and Thier40, compared to that of DMD-BPDS, which is felder4 have determined the heat of combustion of essentially zero. This difference can be explained methyl nitrite, but their value corresponds in by the clectrostatic interaction. The distances precision to an uncertainty in entropy of f 3 e.u.. between the charges on the D M D and BDS ions which is not sufficiently accurate to determine the are almost the same, so that when an ion pair forms, barrier to rotation of the methyl group. W e fell the charge sites of the two ions are very close to that the direct determination of the heat of reeach other. Thus, greater association would be action between methyl alcohol and nitrosyl chloexpected for the DMD-BDS than for DMD- ride to form methyl nitrite and hydrogen chloride, BPDS, where the distance between the two charges reaction 1, mould be a much more sensitive method on the anion is of the order of three times the for measurement of the heat of formation of methyl chhrge separation in the cation. CH,OH(g) NOCl(g) = CH,ONO(g) The values of the limiting conductances are not H C W (1) precise because the salts are hygroscopic, but this uncertainty has little effect upon the other parameters of the equation. The limiting conductance nitrite. In this reaction, the heats of formation of the DMD ion can be computed from Atkinson's of the other participants all have been determined values3J for the BDS and BPDS ions; the two with high accuracy: thus the precision of the values are given in Table 111. The difference of Joule expansion reactant mixing gas calorimeter of about 1% between them probably is due to a small Ogg and Ray5 would be adequate to determine the amount of water still in our sample of DMD- barrier to rotation of the methyl group in methyl RDS; this salt was unusually difficult to dehydrate. nitrite. Experimental Also given in Table I11 are the (uncorrected) Materials.-Methyl alcohol was purified by the method of Stokes radii calculated for the D M D ion.
+
TABLE I11 SINGLEION CONDUCTANCES Salt
DMD-BDS
DMD-BPDS
Xa
-
59.94 48.99
)io
+
74.4 75.1
108R-
lOsR+
3.07 3.76
2.47 2.45
The center-to-center ion pair distances computed from the hydrodynamic radii of DMD-BDS and DMD-BPDS are 5.54 and 6.21 A., respectively; these are higher than the values of UJ of 4.3 and 4.4, respectively. These hydrodynamic dimensions should be larger than the electrostatic because the charge sites are situated near the ends of the prolate ellipsoidal ions and thus the distance of closest approach of the charge sites might be expected to be less than the sum of the mean Stokes radii of the ions. Thus the Fuoss-Onsager eq. (1) can adequately represent data for 2-2 salts in aqueous solution up to concentrations of about 2.5 X 10-3 jl4 to O.O20j,. For the case of bolaform electrolytes, we note that the degree of association is sensitive to the ratios of the charge separations in the two ions, the association being greatly increased when this ratio is near unity.
+
Gillo.6 Nitrosyl chloride was prepared as described previously'by the reaction of nitric oxide with chlorine. Methyl nitrite was prepared as described previously.* Dry hydrogen chloride gas was prepared by the reaction of C.P. sulfuric acid with reagent grade potassium chloride in a vacuum system. Apparatus and Procedure.-The Joule expansion reactant mixing gas calorimeter employed has been described previously.* I n the present case the calorimeter contained a 269.8-m1. gas reaction bottle. The energy equivalent of the calorimeter including 275 ml. of chlorobenzene liquid was found to be 161.O cal./deg. by the heat of water vaporization method which has been described by Ray.$ The value -10,520 cal./mole was used for the heat of vaporization of water a t 25". Reactions were carried out a t 25". The thermochemical calorie exactly equal to 4.184 absolute joules was used in calculations. The calorimeter wa8 filled with gases from a vacuum system which was equipped with
(1) Presented in part a t the America.n Chemical Society Meeting, St. Louis, Missouri, March 21-30, 1961. (2) P. Gray and 31.W. T . Pratl, J . Chem. Soc., 3403 (1058). (3) J. A. Leermakers and H. C. Ramsperger, J. A m . Chem. Soc., 54, 1832 (1932). (4) G. Geiseler and W. Thierfelder, Z. phusilc. Chem. (Frankfurt), 29, 248 (1961). ( 5 ) R. A. Ogg, Jr., and J. D. Ray, J . Phys. Chem., 61, 1087 (1957). (6) L. Gillo, Ann. chim., [11] 12, 281 (1939). (7) J. U. Ray and R. A. Ogg, Jr., J. Chem. Phys., 26, 984 (1957). (8) J. D. Ray and R. A. Ogg, Jr., J . Phys. Chem., 63, 1522 (1959). (9) J. D,Ray, Rea. Sei. Instr., 27, 863 (1956).
