In conclusion, the results of the temperature study ... - ACS Publications

by Everett Douglas scripps Institution of Oceanography, La Jolla, California19 1. (Received October 1.4, 1966). The values obtained from the average...
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NOTES

1931

.80

-

+70

-

.60

-

.50

-

tt0

-

Wtv)

1 - 30 1 '1.20

In conclusion, the results of the temperature study of the capture coefficients of the aromatic aldehydes and ketones are in agreement with the kinetic model proposed earlier.2 The linear correlation of the electron affinities calculated using this model with the half-wave reduction potentials supports the interpretation of the electron-capture response in terms of the electron affinities for compounds which form stable negative ions. The absolute values of electron affinities for five aromatic aldehydes and acetophenone are given. Acknowledgments. This work was financially supported by the Robert A. Welch Foundation. Edward Chen was also a NASA predoctoral fellow.

130

1.40

1.60

1.50

E (ev)

h

Carbon Monoxide Solubilities in Sea Water

Figure 2. Electron affinity us. half-wave reduction potential for the aromatic aldehydes. The compounds are, reading from left to right: cinnamaldehyde, phenantbenealdehyde-9, naphthaldehydel, naphthaldehyde-2, and benzaldehyde. The values obtained from the average intercept are indicated by rectangles, the height a t the rectangle - being- a measure of the standard error. The circles are the data obtained by using a variable intercept with the horizontal lines indicating the standard error limits.

for the polarographic data in dioxane and

EA

=

0.705

f O.lOEi/,

+ 1.67

f

0.17, (Tab

=

-0.018

(6)

in 2-methoxyethanol. (Tab is the covariance term associated with the two parameters shown in the linear equations, eq 5 and 6. In ref 3 it was pointed out that the formation of a solvated charge-transfer complex could not be used to explain a slope which was less than unity. However, of the aromatic aldehydes, the slope is in the greater than unity and would be in agreement with the postulate of complex formation. The affinity Of anthracenea1dehyde-9 can be in Figure and is given in estimated from the Table I in parentheses. From the least-squares estimate of kl/kL and a value for kL, the rate constant, kl, can be determined. The value for k L can be determined from the average intercept and a value for kD. The value of kD is 2.4 X lo3 sec-' SO that the value of kL is 2.4 X lo4 sec-l. With these values and assuming a preexponential temperature dependency for k-1 of Tal/',IC-1 can be determined. The results of this analysis for the compounds exhibiting both an a and fi region are given in Table 11.

by Everett Douglas scripps Institution of Oceanography, La Jolla, California191 (Received October 1.4, 1966)

Carbon monoxide was first reported in the brown alga Nereocystis in 191L3 Since then it has been observed in other algael4v6some other plants,6 and a few of the siphonophores such as the surface-floating Physalia,?P8 a bathypelagic N a n ~ m i a ,and ~ ~ a~ ~benthic form.11 The concentration of this gas in the siphonophore floats has been found to be as high as 93%" of the total gas while in the algae upward to 12% has been r e p ~ r t e d . ~ With this rising interest in the occurrence and utilization of CO, generally considered toxic in biological systems, it has become desirable to measure some of the (1) Contribution from the Scripps Institution of Oceanography, University of California, Ban Diego, Calif. (2) This investigation was supported by Public Health Service Research Grant NO.GM-10521 from the National Institutes of Health and was performed under contract for the United States Navy Electronics Laboratory, San Diego, Calif. (3) S. E.Langdon, J . Am, Chm. Sot,, 39, 149 (1917). (4) M. W. Loewus and C. C. Delwicke, Plant Physiol., 38, No. 4 , 371 (1963). (5) D. J. Chapman and R. 0. Tocher, Can. J. Botany, 44, 1438 (1966). (6) S. M. Siegel, G. Renwick, and L. A. Rosen, Science, 137, 683 (1962). (7) J. B. Wittenberg, BWl. Bull., 115, 371 (1958). (8) J. B. Wittenberg, J . Ezptl. Biol., 37, 698 (1960). (9) G. V. Pickwell, E. G. Barhan, and J. W. Wilton, Science, 144, 860 (1964). (10) G. V. Pickwell, U. S. Navy Electronics Laboratory, Report N ~ 1369, . 1966, (11) E. Douglas, unpublished data. .

I

Volume 71, Number 6 May 1967

NOTES

1932

Table I : Experimental Solubility Coefficients of Carbon Monoxide Cl0/,, = 15.38 1.50'

Av

6.46'

10.00~

19.86'

24.60'

30.OOo

0,02049 0.02043 0.02050 0.02047

0.01913 0.01920 0.01910 0.01914

0.01782 0.01802 0.01780 0.01788

14.96'

0.02216 0.02225 0.02217 0.02219

0,02904 0.02895 0.02894 0.02898

0.02606 0.02590 0.02597 0.02598

0.02422 0,02415 0.02420 0.02419

2.200

6.50'

10.14'

15.25O

20.08'

25.08'

30.70'

0.02744 0.02758 0,02747 0,02750

0.02485 0.02488 0,02512 0.02495

0.02329 0.02328 0.02326 0.02328

0.02127 0.02125 0.02129 0,02127

0.01982 0.01974 0.01976 0.01977

0.01832 0.01829 0.01826 0.01829

0,01725 0.01732 0.01712 0.01723

0.88O

6.10°

10.04'

15.25"

19.86'

25.230

30.05'

0.02753 0.02759 0.02755 0.02756

0.02452 0,02440 0.02440 0.02445

0.02274 0.02269 0.02267 0.02270

0.02085 0.02075 0.02060 0.02073

0.01925 0.01925 0.01914 0.01921

0.01775 0.01779 0.01783 0.01779

0.01684 0.01686 0.01679 0.01683

ClO/,, = 18.60

Av

CP/,, = 20.99

Av

Table 11: Carbon Monoxide Solubility in Sea Water"

-

Temp,

15

O C

16

17

Chlorinity----18 a, carbon monoxide

0.03044 0.03124 0.03084 0,03162 -2 0.02976 0.03014 0.03052 -1 0.03090 0.02910 0,02986 0.02948 0.03024 0 0.02842 0.02878 0,02913 0.02949 1 0,02776 0.02811 0.02846 2 0.02880 0.02713 0,02746 0.02779 0.02812 3 0.02652 0.02684 0.02717 0,02750 4 0.02594. 0,02625 0.02656 0.02686 5 0.02541 0.02572 0.02602 0.02632 6 0.02490 0.02548 0.02519 0.02578 7 0,02440 0.02468 0.02496 0.02524 8 0.02394 0,02421 0.02448 0.02475 9 0.02350 0.02402 0.02376 0.02428 10 0.02308 0.02334 11 0.02359 0.02385 0.02267 0,02292 0.02318 0.02343 12 0.02228 0.02278 0.02252 0.02302 13 0,02188 0.02213 0.02238 0.02262 14 0.02152 0,02176 0.02200 0.02224 15 0.02116 0.02140 0.02 164 0.02187 16 0.02082 0.02106 0.02129 0.02152 17 0.02048 0.02072 0.02094 0.02118 18 0.02016 0.02061 0.02038 19 0.02084 0.01985 0.02030 0.02008 20 0.02052 0.01955 0.02000 0.01978 21 0.02022 0.01926 0.01948 22 0.01971 0.01993 0.01898 0.01920 0.01942 0.01965 23 0.01872 0,01893 24 0.01915 0.01936 0.01847 0.01890 0.01868 0,01912 25 0,01822 0.01844 0.01864 0.01886 26 0.01800 0,01842 0.01822 27 0.01862 0.01780 0.01800 0.01820 0.01839 28 0.01760 0.01780 0.01800 0,01819 29 0.01742 0.01760 0.01778 0.01796 30 " Note that chlorinity is expressed in terms of grams of chlorine per kilogram of sea absorbed by a unit volume of water when the pressure of the gas equals 760 mm.

The Journal of Physical Chemistry

19

20

21 >

0.03004 0.02938 0,02872 0,02807 0.02743 0.02680 0.02620 0,02564 0.02510 0,02460 0.02412 0,02366 0.02322 0.02282 0,02242 0.02202 0.02164 0.02128 0.02092 0.02059 0.02026 0,01994 0.01962 0.01932 0.01904 0.01876 0.01850 0.01825 0.01802 0.01780 0.01760 0.01741 0.01724 water while a is

0.02966 0.02926 0.02862 0.02900 0.02835 0.02797 0.02772 0.02736 0.02675 0.02709 0.02648 0.02614 0.02588 0.02556 0.02532 0.02501 0.02450 0.02480 0.02432 0.02402 0.02356 0.02384 0.02339 0.02312 0,02296 0.02270 0.02230 0.02256 0.02216 0.02192 0.02178 0.02153 0.02116 0.02140 0.02104 0.02080 0.02070 0.02046 0.02036 0.02014 0,02002 0.01980 0.01971 0.01949 0.01917 0.01940 0.01910 0,01888 0.01882 0.01860 0.01854 0.01832 0.01828 0.01806 0.01804 0.01782 0.01780 0.01760 0.01760 0.01740 0.01740 0.01720 0.01722 0.01702 0.01706 0.01688 given as volume of gas (STPD)

NOTES

1933

Some Observations on the Kinetics of Hydrogen

100

Iodide Addition t o 1,3- and 1,4-Pentadienel

00

x = 30.70° C

60

by Kurt W. Egger and Sidney W. Benson

I

4

40 Department o j Thermochemistry and Chemical Kinetics, Stanford ReseaTch Institute, Menlo Park, California 94086 (Received September 81, 1066)

v)

aC2O 0

0246810

30 TIME (min.)

Figure 1.

physical properties of this gas. In this report one of these parameters, the solubility coefficients in three sea water chlorinities at seven temperatures per chlorinity, is given.

Experimental Section The microgasometric method used has been described in detail earlier.1211aeThe absorption chamber has been enlarged to employ 8 ml of water in order to maintain the same accuracy as obtained using distilled water.lab Figure 1 shows the rate of solution of CO in the absorption chamber, illustrating that 30 min is ample time for equilibration to occur. The procedures used for obtaining gas-free sea water and the chlorinity determinations are detailed in an earlier work. lss The purity of the CO was determined using a Scholander 0.5-cc gas analyzer14 and microgasometric analyzer16showing the gas to be at least 99.7% pure. An independent method utilizing palladium chloride also gave a purity of greater than 99%.6

Results and Discussion The experimental solubility coefficients are listed in Table I. Smooth curves were fitted on these points from which the values from -2 to 30" were taken. From these values the relations between solubility and chlorinity were graphed and the values from -2 to 30" in chlorinities ranging from 15-21"/,, were obtained. These are given in Table 11. The only other solubility determinations of CO are those of Winkler for distilled water. 18,17 (12) E. Douglas, J . Phye. Chem., 68, 169 (1964). (13) (a) E. Douglas, ibid., 69, 2608 (1965); (b) for critical discussion of systematic errors refer to the original paper.12 (14) P. F. Scholander, J . Bwl. Chem., 167, 235 (1947). (15) P. F. Scholander, L. Van Dam, C. L. Claff, and J. W. Kanwisher, BWZ. Bull., 109, 328 (1955). (16) L. W. Winkler, Z . Physik. Chem. (Leipaig), 55, 344 (1906). (17) "Handbook of Chemistry and Physics," 39th ed, Chemical Rubber Publishing Co., Cleveland, Ohio, 1957.

We wish to report some quantitative kinetic information on the addition of HI to olefins, obtained complementary t o reported studies of the iodine atom catalyzed isomerization2&rband dimerization20 of n-pentadienes in the gas phase. The rate of addition of HI to either 1,3- or 1,Cpentadiene was checked as a possible side reaction in these studies. We found that, during the isomerization of 1,4-pentadiene in the presence of iodine at temperatures between 420 and 515"K, 5-10Oj, monoolefins had been produced, according to diolefin

+ 2HI

olefin

+ 12

The mechanism of this over-all type of reaction has been shown to consist ofid 1

diolefin

+ HI JcRI -1

(slow)

(A)

(fast)

(B)

and

RI

+ HI

2 -2

RH

+ I:,

with kl as the rate-controlling step. The intermediate alkyl iodide reacts rapidly and almost quantitatively with HI, forming the parent saturated compound, and in the case of diolefin as starting material, monoolefin is produced. Equation B was shown to be, in fact, a composite of

RI

+ IJR.

+

(B1)

and

R.

+H I Z R H +I

032)

As both steps, BI and Bz, are fast compared to L, they do not alter the simple second-order kinetics. Rate constants, kl, were calculated from pressure measurements, as only the rate-controlling step A leads to a pressure change. The formulation given (1) This work has been supported in part by Grant No. AP00353-01 from the Air Pollution Division of the U. S. Public Health Service. (2) (a) K. W. Egger and S. W. Benson, J . Am. Chem. SOC.,88, 241 (1966); (b) K. W. Egger and 5. W. Benson, ibid., 87, 3314 (1965); (c) K. W. Egger and 8. W. Benson, unpublished data; (d) S. W. Benson, J. Chem. Phys., 38, 1945 (1963).

Volume 71, Number 6 M a y 1967