NOTES
June, 1963
6 , and setting g
= 2.5 and h = 2. The function II is insensitive to g and h within the limits set by Weber for these two coefficients. Furthermore, these four sets of data represent a combination of techniques of pressure measurement, namely, the Pirani gage, an adsorption technique, the McLeod gage, and a vapor pressure technique. An adjustment of a! and p has been made on the basis of these data alone. Values of p were first calculated wit,h a! = n/128 for each data point in the region y < 4. 'The average value of p so obtained was used to calculate an average value of a! for the data in the region y > 4. The calculation was repeated until consistent average values of the coefficients were obtained (Table I). The final form of equation 2 was
0 . 0 3 0 0 ~ ~ 0 . 2 4 5 ~ -~ 1 2y TABLE I THERMAL TRAKSPIRATION COSSTAKTS CALCULATED FROM DAT.A
Source
Gas
0.245) (Q = 2 . 5 ) ( h = 2) (2/ > 4 )
Ref. 10 Ref. 11 Ref. 14, 15 Ref. 16
Hz, He
,..
He, Ne Kr Xe
=
N
1.1 X 105/T2
X 103/2.33T)N 5.6 X 102/T
U2/UHe2
$?g
T
X 1O3,'/2.33T)?
a(me'
P H e = P(UHe2
(Ti
=
+ '5"4/2
T/128,
a
N
7/12,
gHe2 N
5X.2
The rather different relations generally used with the Liang e q ~ a t i o n ' ~are J ~ not of sufficient generality to apply if T Bdiffers appreciably from room temperature. The small correction factor for the Liang equation a t low pressuresls may be accounted for by the fact that p actually approaches unity only a t very low pressures.
THE C0UPLIh:G OF NJCLEAR SPINS OF PROTOi'r'S IT\' TWO '4LLEKES
P
(I
(p
C Y H ~=
(18) M. J. Bennett and F. C. Tompkins, T r a n s . F a i a d a y Soc., 53, 1136 (1957).
+ +
+
1361
( a = 0.0300) (Q = 2 . 5 ) (h = 2) (2/ < 4 )
0.181 .302 .262 ,234 ,245
0.0271 ,0322 .0306 Av. ,0300
It is seen from the selected values in Table XI that there is little choice between the fitted coefficients in equation 4 and the approximate values listed under
BY R. K. KULLNIG AND F. C. SACHOD Sterling-Winthrop Research I n s t i t u t e , Kensselaer, N e w Yorlz Recetzed October 1 7 , 1969
We have observed the coupling of nuclear spins of the allenic protons in 2,2-dimethyl-3,4-octadienal (I) and found the magnitude of the coupling constant ( J = 6.3 c.P.s.) in good agreement with the findings od previous investigators of alleiiic compound^.^-^ Un-
TABLEI1 SELECTED VALIJESOF THE GENERALIZED COORDINATES FOR THERMAL TRANSPIRATIOK Y
II
0.01 .02 .04 .OB5 .1 .2 .4 .65
1 .o 2 .O 4.0 6.5 10 20 40 65 100
a = n/128 p = T/l2 Q = 2.5 h = 2
0.993 ,985 ,971 .956 ,937 ,889 ,819 ,757 ,687 ,549 .375 ,252 ,158 ,061 ,0195 ,0082 ,0037
o = 0.0330
p
0.245 2.5 h = 2
= Q =
0.993 ,985 ,972 ,957 ,938 ,890 .823 ,761 ,693 .553 ,373 ,245 ,150 ,055 ,0169 ,0070 ,0031
n I
, 800
I 500
Ho+
equation 1. For the four preferred sets of data the average deviation of from values calculated with equation 4 is 0.016; in the region :L < y < 5, the average deviation is 0.022. Equations 3 and 4 may be used to estimate the thermal transpiration ratio, P I / P ~for , any gas for which the prerequisite viscosity dat'a are available. Over the entire pressure range the value of p has the limits 1 < p < 1.25. I€p is arbitrarily set a t unity, one obtains what is essentially Liang's empirical equation, 17 along with the following relations for Liang's coefficients ( 1 7 ) S . C . Liang, J . Phys. Chem., 57, 9 1 0 (1953).
400
300
200
too
0 CPS
Fig. 1.-Proton resonance spectrum of 2,2-dimethyl-3,4-octa dienal. Proton signal of CjH and C3H insert ( a )neat; insert (b' 20% solution in CCI,
fortunately, experiments which are suitable to determine the sign of the coupling constant are beyond the scope of the Varian A-60 spectrometer. The (1) T h e samples u e r e obtained from E a s t m a n Chemical Products, I n c , Kinnswort Tennessee -. (2) E. R. Whipple, J. H. Goldstein, and W. E. Stewart, J . Am. C h e m . Soc., 81. 4 7 6 1 11959). , , ( 3 ) S. L. M a n a t t and D. 13. Elleman, ibid., 84, 1579 ( 1 9 6 2 ) . (4) E. I. Snyder and J. D Roberts, ibzd., 8 4 , 1682 ( 1 9 6 2 ) .
1362
Vol. 67
NOTES TABLE I 2,2-DIXETHYL-3,4-OCTADIENAL
8""
O=CH-
-CH=C=CH-CHZ-CH~-CH~
O=CH562 560 1 Singlet sharp
68 67 6 Singlet sharp
304.2 317.7 302.2 317.0 1 1 See inBert of Fig. 1
43-135 45-137
Neat 20% in CC1, 7 Intensities Complex of bands partially resolved
}
from TNS (internal standard
C.P.S.
TABLE I1 2-BUTYL-2-ETHYL-5-METHYL-3,4-HEXA4DIENAL
/CH3
Bu(n) O=CH-h-CH=C=C,,
I
Et
CHD
I1
Bu( n )
CH3
I I
O=CH-
-C -
562 558 1 Singlet sharp
CH=C=
' 6
\
Et 3i-100 37 -100
CHs
295 292
1-1
1
Complex partially resolved
Septet resolved
Neat 102 20% in CC1, 6 Intensities Doublet resolved
102
}
c.p.s. from TMS (internal standard)
the C3 proton of I1 is a well resolved septet (cf. Tables I and 11).
RIUTUAL DIFFUSION I N KOK-IDEAL LIQUID MIXTURES. IV. METHAKOLCARBON TETRACHLORIDE AND DILUTE E T H A N O L CARBON TETRACHLORIDE SOLUTIOSS BY D. K.ANDERSONAND A. L.BABB Department of Chemical Enganeerang, Unzversaty of Vashznyton, Seattle, Washzngton Receaaed August 80,1962
In previous papersl.2 the authors presented diffusion data for associated binary liquid systems. As part of this continuing program, diffusivities have been measFig. 2.-Proton resonance spectrum of 2-butyl-Z-ethyl-5ured for dilute solutions of ethanol in carbon tetrachlornethyl-3,4-hexadienal. Proton signal of C3H: insert (a). ride and the methanol-carbon tetrachloride system coupling between the spins of the C6-methyleneand the over the entire concentration range. C6-proton (J6,6= 6.5 c.P.s.) is the same as that of The mutual diffusion coefficients were measured comparable protons in other 01efins.~ The coupling using a Mach-Zehnder diffusiometer described fully between the spins of the C6-methylene and the C3- elsewhere. Temperatures were controlled a t 25.0 f proton (J3,6= 3.3 c.P.s.) compares well with a com0.05'. The reagent grade solvents were obtained from parable parameter which was determined from the blallinckrodt Chemical Works and were used without n.m.r. spectrum of 3-methyl-l,2-butadiene by Snyder further purification. and R ~ b e r t s . ~ Similarly, the spin-coupling between The diffusivities were obtained by measuring the the protons of the terminal methyl groups and the interdiffusion of two solutions of very nearly equal conallenic proton in 2-butyl-2-ethyl-3-methyl-3,4-hexa- centration. The measured value was taken to be that dienaI (1I)lwas found to have about the same coupling of a solution with a concentration equal to the average of constant ( J = 3.0 c.P.s.). the two. The results are given in Tables I and 11. KOevidence of any spin-coupling between the allenic Although data were previously available4 for the protons and the protons of the substituents on CZ of ethanol-carbon tetrachloride system, a seriep, of detereither compound could be detected. The signal for (1) D. K. Anderson and A. L. Babb, J . Phys. Chem., 65, 1281 (1961). the C2-methyl groups of I was sharp, and the signal of (2) D. I
