A Study of Organic Parachors. V. Constitutive Variations of the

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KATHEKINE OWEN,OSBOKNE Ti. QUAYLEAND WILLIAMJOSIAH CLEGG

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[CONTRIBUTION FROM THE CHEMlSTRY

Vol. 64

DEPARTMENT OF EMORY UNIVERSITY ]

A Study of Organic Parachors. V. Constitutive Variations of the Parachors of a Series of Normal Ketones' BY KATHERINE OWEN,OSBORNE R. QUAYLEAND WILLIAMJOSIAH CLEGG~ It has been shown in the present series of papers and by others that the parachor is of a highly constitutive nature and varies with the ciegree of unsaturation of the compounds considered. Definite values may be assigned t o specific groups, And tersuch as the tertiary alcohol, )C-OH, tiary chloride, 7C--Ci, \ linkages, which vary with the alkyl groups a t t a ~ h e d . ~ . The ' present paper is concerned with the determination of the parachor values of the fifteen normal chained ketones of eleven or less carbon atoms and with the evaluation of the constitutive variations in the value of the carbonyl group as different alkyl groups are attached. -

0 82301 'c,

Eight of the ketones studied were prepared by standard methods in this Laboratory and seven were of the highest grade commercially available (Eastman Kodak Co.). All were refractionated. The boiling ranges are given in Table I. The density and surface tension of acetone were determined a t 24.80" only. Methyl ethyl ketone was measured a t 34.83, 45.10 and 50.15' and values for 24.80" were determined by extrapolation. The densities and surface tensions of the other ketones were determined a t 24.80, 34.85 and 50.15" (Table I). The maximum bubble pressure method was used for the determination of surface tension. Readings were checked by independent observers with a maximum deviation of 0.2%.

0.8130

26.00

0.8030

25.00

d

;L

24.00

0.7930 23.00

22.00

0.7730

'\

I

25

Fig. 1.-Variation

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35 T , "C.

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of density with temperature.

(1) The authors wish to express their gratitude to Prof. E. Emmet Reid, research consultant t o the department, for his interest in aud

suggestions in connection with the problem. (2) Abstracted from material presented by William Josiah Clegg t o the Graduate faculty of Emory University in partial fulfillment of the requirements for the degree of Master of Science, June, 1940. Present address, University of Texas, Austin, Texas. (3) K. Owen, 0. R. Quayle and E. M. Beavers, THISJOURNAL, 61, 500 (1939). (4) 0. R . Qu:ivle, IC. Owen and E. M. Sesvers, i b i d . , 61, 3107 (1939).

21.001

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35

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IAI 50

T," C . Fig. 2.-Variation

of surface tension with temperature.

The parachor values (Table I) were calculated using the equation P = M y l / d / ( D - d ) , where is the surface tension, Jf the molecular weight, D the density of the liquid, and d the density of the vapor a t the same temperature. The density of the vapor is relatively small and is included in the calculations only with those ketones where its

PARACHORS OF NORMAL KEXONES

June, 1942

BOILINGPOINTS, Ketone

TABLE I DENSITIES, SURFACE TENSIONS AND TEE

Boiling range,

Pressure,

OC.

mm.

55.2-55.5 78.3-78.5

741.8 736.3

T

D

PARACHORS OB d

24.80 0.78% 0.0007 .7979 24.80 .0004 .7899 34.85 .0006 .7736 50.15 .OOlO .8034 24.80 MP 100.9-101.0 741.8 ,0003 34.85 .7936 .0004 50.15 ,7785 .0006 127.1-127.3 24.80 ,0002 MB 748.2 ,8105 34.85 .8014 * 0002 .7874 50.15 .0003 148.0-148.2 741.1 24.80 .8118 MA 34.85 .OOOl .8035 50.15 .7901 .0002 24.80 .8097 ,0002 EE 100.0-100.2 749.7 34.85 .0004 ,8000 50.15 .0006 .7848 24.80 .0002 .8113 120.9-121.1 747.9 EP 34.85 .0003 .8021 .0004 50.15 .7877 143.9-144.1 742.7 24.80 .oO01 .8163 EB 34.85 .0002 .8077 50.15 .0002 .7941 167.0-167.1 24.80 EA 746.2 .8188 34.85 .8103 50.15 .7974 141.8-142.0 24.80 .8147 748.6 PP 34.85 .8060 .0002 .0003 50.15 .7925 161.9-162.1 24.80 .8146 748.5 PB 34.85 -8065 50.15 .7939 88.8- 89.2 .8190 PA 25.5 24.80 .8108 34.85 .7982 50.15 .8174 24.80 BB 102.3-102.7 44.3 .8093 34.85 .7966 50.15 .8203 743.0 24.80 BA 205.0-205.1 .8125 34.85 50.15 ,8003 120.9-121.0 25.3 .8231 24.80 fiA 34.85 .8153 50.15 .8035 Values determined by authors. Mean values of Cowan, Jeffery and Vogel. MM ME

value. is appreciable, as indicated in Table I. The variations of densities, surface tensions and the parachors with temperature are shown respectively in Figs. 1, 2 and 3. The parachor values of eight of the ketones in Table I are in striking c o n h a t i o n of the mean values reported by Cowan, Jeffery and Vogel6 upon these ketones a t comparable temperatures. (5) Cowan, Jeffery and Vogel, J . Chcm. Soc., 171 (1940).

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FIFTEEN NORMAL KETONES Y

22.99 23.97 22.88 21.13 22.41 23.38 21.68 25.50 24.32 22.72 26.17 25.02 23.48 24.73 23.74 22.11 25.03 24.01 22.32 25.72 24.69 23.17 26.21 25.22 23.75 25.47 24.40 22.81 25.77 24.85 23.55 26.30 25.31 23.89 26.30 25.29 23.85 26.56 25.60 25.24 27.05 26.20 24.78

Pa

Pb

162.1 199.8 199.9 200.2 238.4 238.8 238.9 277.8 277.6 277.8 318.1 317.9 318.2 237.3 237.8 238.2 276.2 276.5 276.5 315.0 315.2 315.2 354.3 354.6 355.0 314.9 314.9 315.0 354.6 354.9 355.8 393.3 393.5 393.9 394.0 394.1 394.6 432.5 432.6 433.2 471.8 472.6 472.9

161.6 199.5

238.0

277.5

319.5

237.4

277.3

315.1

Although the surface tensions were measured by a different method (capillary rise), the maximum deviation in the values is 0.3%. Cowan, Jeffery and Vogel noted a large divergence of their values from the calculated values, based upon the constants of Mumford and Phillips,6but did not have available as complete series. The parachor value for the carbonyl group in (6) Mumford and Phillips, ibid., 2112 (1929).

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KATHERINE OWEN,OSROKNE I