I.VDUSTRIAL AND ENGINEERING CHEMISTRY
5 06
16-Van Slyke and Bosworth, N . Y . Expt. S f a . Ann. Rept., 1918, Tech. Bull. 26. 17-Van Slyke and Winter, Ibid., Ann. R e f t . , 1920, Tech. Bull. 83. l&Gmelin-Kraut, “Handbuch der anorganischen Chemie,” Vol. 11, Sect. 2, 314 (1909). 19-Whymper, “Cocoa and Chocolate,” Chap. XXI, p. 214, P. Blakiston’s Son & Co., Philadelphia, 1912. 20-Van Slyke and Hart, N . Y . Expl. Sta., Bull. 261 (1905). 2l-Blyth, “Foods, Their Composition and Analysis,” p. 363 (1909). 22-Loeb, Jacques and Loeb, R. F., J . Gen. Physiol., 4, 189 (1921). 23-Clark, “The Determination of Hydrogen Ions,” Williams & Wilkins C o . , Baltimore, 1925. 24-Csonks, Murphy, and Jones, J . A m . Chem. Soc., 48, 763 (1926). 2&Hijikata, J. B i d . Chcm., 61, 165 (1922). 26--AlmBn, Upsala IUkarefdranings Fdrhandlinger, 1870.
Vol. 19, No. 4
27-Taraszewics, Dorpat, 1872. 2&Liborius, Ibid. 29--Girgensohn, Ibid. 30-Ritthausen, J . prakt. Chem., 16, 329 (1877). I l - S t e n b e r g , Nord. Med. Ark., 9, No. 7 (1882). 32--Munk, Vlrchow’s Arch., 184, 501 (1893). 33-Camerer and SBldner, 2.B i d , 38, 43 (1896). 34-Camerer and Sdldner, Ibid., 33, 535 (1896). 35-Camerer and Soldner, Ibid., 36, 277 (1898). 36-Simon, 2.physiol. Chem., 88, 466 (1901). 37-Trillat and Sauton, L’industrie lailibre, 32, 107 (1907). 38-Bleyer and Kallmann, Biochem. Z.,168, 459 (1924). 39-Ringer, Chcm. WeekbZad, 6 , 4 4 6 (1909). 40-Clark and Lubs, J . B i d . Chem., 25, 479 (1916). 4l--McIlvaine, Ibid., 49, 183 (1921).
New Glycerol Tables’ Tables for Specific Gravity and Per Cent of Glycerol-Thermal Expansion of Aqueous Solutions in Terms of Specific Gravity By L. W. Bosart and A. 0. Snoddy THEPROCTER & GAMBLE Co., IVORYDALB, OHIO
Lenz4 evidently did not try EVERALyears ago one New tables are given for the specific gravity and per to hold his temperature close of the writers called atcent glycerol, both apparent and true, of mixtures of enough to give very accurate tention to the fact that glycerol and water of varying strengths at different results. Strohmer’ did not there was no s a t i s f a c t o r y temperatures. Very pure glycerol was used and the attempt to give his results t a b l e e x t a n t showing the authors believe that their tables are more accurate beyond the third place. Gera m o u n t s of p u r e glycerol than any heretofore published. lach’s table at 20”/20° C. has present in mixtures of glycerol The table of Nicol is considered the best of those been purposely omitted as it and water of different denpublished previous to this, but i t has some values which has been shown to be quite sities.* There were then and are sufficiently incorrect to greatly impair its usefulinaccurate.2 Gerlach’s table are a t present several tables ness. a t 15’/15O C. has been rein use, of which that of GerA table is also given showing the rate of expansion garded as the best now in use, lach at 15O/15” C. was recof mixtures of glycerol and water of varying concentrabut apparently he did not tions from 15’ to 25’ C. A means is thereby given for ommended as being probably attempt accuracy beyond the the most accurate. comparing all glycerol tables with one another. third place, and his results The various tables are made A correction is made to some published figures on the calculated to the fourth place specific gravity of glycerol. up for a number of different in most cases agree poorly temperatures and could not w i t h o u r own. Skalweit6 be readily compared. In most cases the experimental work has been done in such a manner does not state definitely that he used water at 15’ C. as unity, that the specifib gravity determinations were not accurate but it is to be presumed that he did. We have endeavored to clear up this situation, starting beyond the third decimal place, and, indeed, greater accuracy was usually not attempted, although some of the tables con- with a glycerol of the highest purity, establishing its specific structed from these results gave figures in the fourth decimal gravity very accurately a t 15’/15”, 15.5°/15.50, 2Oo/2O0, place. Nic01,~however, was able to get results that agreed and 25’/25” C., and have made up from this glycerol and well in the fifth place and considered his results to be accurate water mixtures of various strengths, and have determined the certainly to the fourth. His values-except for 90, 80, 70, specific gravities of these mixtures. We have shown both and 60 per cent glycerol-are in rather good agreement with the apparent and true specific gravities and have given the those of the writers, which are given in this paper. On the true specific gravities of glycerol a t 15’/4’ and 20°/4” C. whole, they agree better than any so far published. In We have, moreover, calculated from the data found the rate some of the tables it is not clear whether or not water a t the of expansion of glycerol and of mixtures of glycerol and water same temperature as that a t which the glycerol has been tested of varying strengths in terms of their specific gravities. is taken as unity. It is likewise not always clear whether the Preparation of Pure Glycerol results show apparent or true specific gravities-i. e., specific gravities reduced to vacuum. Probably apparent specific I n order to obtain a quantity of pure glycerol sufficient for gravity is meant in most cases, although this is not a factor unless accuracy is attempted beyond the third decimal our work, we first procured a very pure commercially distilled place. In Table I the most frequently quoted tables are product having a specific gravity of 1.2629 at 15.5”/15.5‘ C. shown, giving the specific gravity for every 10 per cent. (apparent) and containing 98.7 per cent glycerol by the biThe authors’ values at 15”/15’ C. and 2Oo/2O0 C. for ap- chromate analysis. This glycerol had a slight yellowish color. It was bleached parent specific gravity are given alongside for ready comwith a carbon bleach and then distilled a t 1.7-2.0 mm. presparison.
S
1 I
Received November 13, 1926. THISJOURNAL, 13, 944 (1921). Pharm. J . Trans., [3] 18, 302 (1883).
‘ 2.anal. Chem., 19, 297 (1880).
6
Monafsh., 5, 61 (1884). R e p n t . anal. Chem., 6, 17 (1885).
INDUSTRIAL AND ENGINEERI-VG C H E M I S T R Y
April, 1927
sure, keeping only the middle fraction. This middle portion was redistilled in the same manner, again retaining only the middle fraction, which we considered to be glycerol of the very highest purity. The distilling flask, condenser, and receiver were all of Pyrex glass. The boiling point of this fraction was 141-144" C. (uncorrected) at 1.7-2.0 mm. pressure, the entire thermometer being inside the distilling flask. The glycerol was distilled in a slow current of oxygen-free nitrogen dried with sulfuric acid and phosphorus pentoxide from a 5-liter distilling flask through an air condenser 1 meter long which was sealed to the flask. No stoppers were used about the flask, the gas inlet, the thermometer, and McLeod gage being sealed to it. The condenser was attached to a Bogert distilling receiver, which served to separate the fractions, and vacuum was obtained by means of a Hyvac pump which was connected by means of a glass tube 1 meter long and 4 cm. internal diameter containing calcium chloride and phosphorus pentoxide to a 2-liter flask two-thirds full of sulfuric acid which was connected to the receiver. The course of the uncondensed gas was, therefore, through the receiver, sulfuric acid, one-half meter of calcium chloride, one-half meter of phosphorus pentoxide, to the pump. The glycerol was stored in the flask in which it was caught and came in contact only with air which had come through sulfuric acid and the long tube of calcium chloride and phosphorus pentoxide, the vacuum being broken only when the glycerol was cold. The comparison of specific gravity and the amount of glycerol found by the bichromate method showed the raw material to be practically free from glycol, and the fact that it was distilled under the very low pressure of about 2 mm. would insure that no polyglycerol was formed. The end product could, therefore, contain only extremely small amounts of foreign matter. The glycerol was charged into the pycnometer by being forced out of the flask by means of dried air, and as the pycTable I-Various GLYCEROL Per ceni 100 90 bO
70 60 50
40
30
20
10
LEHZ 12-14°/150 C. 1.2691 1.2425 1.2159 1.1889 1.1582 1.1320 1.1045 1.0771 1.0498 1.0245
STROHXER 1 7 . 5 ° / 1 7 . 5 0 C. 1.262 1.236 1.210 1,182 1,151 1.128
... ... ... ...
507
Specific Gravity Determinations
In order to economize space, only the results calculated to even per cents are given. Determinations in most cases were made in duplicate with two different pycnometers, each of the Geissler type, capacity approximately 50 cc. Table I1 shows the results obtained. They are given in the fifth decimal place, since the agreement is usually within 5 in the B t h place, although there is not always such close agreement. In the final tables (Table HI), they are given to the nearest 5 in the fifth place as this is considered to be about the limit of accuracy. Although the tables for the specific gravity and per cent glycerol are, we believe, usually given for the apparent specific gravities, we give in Table 111both the apparent specific gravities using brass weights and weighing in air, and the corresponding true spec5c gravities. The weights used were corrected to agree with a set of weights tested by the Bureau of Standards. The water used in the pycnometers for reference at different temperatures and for mixing with glycerol was obtained by redistilling ordinary distilled water to which a little alkaline potassium permanganate had been added, using only the middle third of this water. It was distilled, caught, and stored in Pyrex glassware. It was always boiled out shortly before use. After mixing water with the glycerol, it was necessary to allow the mixture to stand several days, in the case of high glycerol concentrations, in order to free it of air bubbles. Determinations were made a t 15"/15", 15.5"/15.5', 20"/20", and 25'/25' C. for every 10 per cent and also for 97.5 and 95 per cent glycerol. I n determining the specific gravities the pycnometers with their contents were placed in a water bath, which was held constant a t the desired temperature * 0 . l o C. by means of a tested thermometer graduated in one-tenth degrees. They were left in the bath sufficiently long to insure their taking
Tables for Specific Gravity a n d Per Cent Glycerol GERLACH 1,j0/15O C. 1.2683 1.2400 1.2130 1,1850 1,1570 1.1290 1.1020 1.0750 1.0490 1,0245
nometer was rapidly filled, glycerol entering it was exposed to undried air for only a very short time. Glycerol in the storage flask never came in contact with moist air. Preparation of Glycerol-Water Mixtures
Mixtures were made to contain 90, 80, 70 per cent, etc., also 97.5 and 95 per cent glycerol. In doing this, a sufficient amount of glycerol was transferred t o a previously weighed glass-stoppered weighing bottle and water added to make up the proper percentage of glycerol. Toward the end of this addition, moist air was blown into the mouth of the weighing bottle to be absorbed by the glycerol in order not to add too great an amount of water. Sometimes the amount of water added slightly exceeded that desired, in which cases the specific gravity determination was made on this diluted portion and calculated back to the even percentage sought. The resulting glycerol was seldom out more than 0.01 or 0.02 per cent, the greatest variation from the even percentage sought being 0.041 per cent.
2 0 ~ / 2 0c.~
SKALWEIT 150/150 c.
AUTHORS 150/150 c.
AUTHORS 20"/200 c.
1.26348 1,23720 1.21010 1.18293 1.15561 1.12831 1.10118 1.07469 1.04884 1.02391
1.2650 1.2398 1.2125 1,1855 1.1570 1.1290 1.1020 1.0750 1.0490 1.0240
1.26557 1.23980 1 21290 1.18540 1.16770 1,12955 1,10255 1.07560 1.04935 1.02415
1.26362 1.237.55 1.21OYO 1.18355 1.15505 1.12845 1.10135 1.07470 1.04880 1.02395
NICOL
I
on the temperature of the bath throughout. This was from 40 to 60 minutes for glycerol of the higher concentrations. After removing the pycnometers from the bath, they were allowed to stand for one hour beside the balance before weighing. The balance was kept in a room whose temperature was maintained a t about 15' C. This was found to be necessary, as otherwise there was danger that the expansion of the contents would burst the pycnometer or blow off the cap. Our results for pure glycerol are higher than those found in the tables usually consulted. They agree, however, with the figure obtained by A. C. Langmuir12who found 1.2653 a t 60"/60' F. or 15.56"/15.56"C., which is in agreement with our result 1.26532 a t 15.5"/15.6' C. Langmuir's figure would equal 1.2655 a t 15'/15" C. which also agrees with our own figure. We conclude, therefore, that Gerlach's result 1.2653 a t 15'/15" C.-which was later verified by Grun and Wirth7 who found 1.2663 and 1.2652-is too low. From our results, we have calculated the true specific 7
Z. ongew. Chem., S a , 59 (1919).
INDUSTRIAL A N D ENGINEERING CHEMISTRY
508
gravity of pure glycerol a t 15"/4" and 20"/4" C., and find, respectively, 1.26415 and 1.26110. In Landolt-Bornstein's tables the most probable values are given as 1.2640 and 1.2609, respectively.
temperature between 15' and 25" C. when the determination has been made at another temperature. For calculating from a higher to a lower temperature, the formula is
Calculation of R a t e of Expansion
Having found the specific gravity of glycerol of varying strength from 0 to 100 per cent, it is clear that we have the means a t hand for calculating the rate of expansion or change in specific gravity per degree of glycerol and water mixtures of varying strengths a t temperatures between 15" and 25" C. The following formula was used to make the calcitlation for the rate of expansion of glycerol between 15" and 25" C.: B = - dc - ab ( T - t)c
TO T to = specific gravity of glycerol a t t
in which a = specific gravity of glycerol a t
d b = specific gravity of water a t T o c = specific gravity of water a t t o B = change in specific gravity of glycerol per degree T = higher temperature of specific gravity determination t = lower temperature of specific gravity determination
. transposing the values in the above equation, formulas be derived for obtaining the specific gravities a t any Table 11-Per
d =
No.
TEMPERATURE"
ab
+ Bc (T - t ) C
For CalcuIating fmm a lower to a higher temperature, the formula is a =
dc
- BC ( T - t ) b
Using these formulas and knowing the rate of expansion of glycerol solutions of different concentrations, the results given in the various tables can be reduced to a common basis for comparison. In Table IV, the rate of expansion is given for glycerol of different concentrations. It will be seen that the results on glycerol between 95 and 100 per cent agree closely with those of Comey and Backus* who found 0.000612 a t 15.5-20" C. and 0.000617 a t 15.525" C. Besides the rate of expansion from 15" to 20" and from 15' to 25", that from 20" to 25" C. is given. From this 8
THIS JOURNAL, 1, 11 (1910).
C e n t Glycerol a n d Specific Gravities, Apparent a n d True, at Different Temperatures SPECIFIC GRAVITY
GLYCBXOL
Vol. 19, No. 4
Apparent
Apparent average
PYC-
NOMETER
Reduced to vacuum
No.
SPECIFIC GRAVITY
T%vz-
Apparent
Apparent average
Reduced t o vacuum
1.15768
.15750
1.15745
.15727
1.15602
,15584
1.18461
.15443
1,12984
,12969
1.12969
.I2054
~~
Pcr cent 100
0
95
1 2 1 2
1 2 1 2 1 2 1 2
15 15 15.5 15.5 20 20 25 25
1.25915 1.25913
1.25914
1.25883
1.isis9
1.25889
1.25858
1.25715
1.25683
1.25556
1.25526
1
1.25273 1.25268 1.25263 1.25248 1.26237 1.25243 1.25080 1,25065 1.25074 1.24816 1.24898 1.24909
1.26268
1.25238
1.25243
1.25213
1 1 2 1
15 15 15 15.5 15.5 15.6 20 20 20 25 25 25
1 2 1 2 1 2 1 2
15 15 15.5 15.5 20 20 25 25
1,23950 1.23947
1
15 15 15.5 15.5 20 20 25 25
2
I 1 2 1 1 2
90
80
2 1 2 1 2 1 2 1
70
2 1 2 1 2 1 2 a
Per cent 60
1.26557 1.26567 1.26535 1.26530 1.26364 1.26360 1.26203 1.26200
1 2
97.5
c. 15 15 15.5 15.5 20 20 25 25
1 2
15 15 15.5 15.5 20 20 25 25
1.25717 1.25713 1.25558 1.25554
1.26557
1.26526
1.26532
1.26501
I.26362
1.26331
1.26201
1.26170
40
1.25046
1.24908
1.24879
1.23948
1.23920
1.15767 1.18770 1.15746 1.15745 1.15601 1.15604 1.16461 1.15462
1 2
15 15 15.5 15.5 20 20 25 25
1.12985 1.12983 1.12973 1.12965 1.12844 1.12843 1.12721 1.12717
1 2 1 2 1 2 1 2
15 15 15.5 15.5 20 20 25 25
1.10253
1 2
15 15 15.5 15.5 20 20 25 25
1.07559 1.07559 1.07551 1.07542 1.07470 1.07468 1.07396 1.07391
15 15 15.5 15.5 20 20 25 25
1.04940 1.04934 1.04932 1,04934 1.04881 1.04880 1.04841 1.04835
15 15 15.5 15.5 20 20 25 25
1.02421 1.02413 1.02420 1.02411 1.02396 1.02390 1.02376 1.02369
1 2 1 2 50
1.25073
c. 15 15 15.5 15.5 20 20 25 25
1 2 1 2
30
1 2 1 2 1 2
1 2 1 2 1 2
1.23921
1.23893
1.i3j55 1.23591 1,23583
1.23755
1.23727
1.23587
1.23559
1 2 1 2
i.iii9i 1.21259 1,21257 1.21088 1.21090 1.20923 1.20924
1.21291
1.21266
1.21258
1.21233
1 2 1 2
1.is921
1.21089
1.21064
1.20923
1,20599
1.18638
1.18517
1.18518
1.18496
1.18354
1.18332
In every case water at the same temperature is taken as unity.
20
10
1 2 1
2 1 2 1 2
1.12843
.12828
1.12719
1.12704
1.10253
1.10241
1.10245
1.10233
1.10137
1.10125
1.10042
1.10030
1. io245 1.iOi37 1. io642
...
1.07859
1.07550
1.07546
1.07537
1.07469
1.07460
1.07393
1.07384
1.04937
1.04931
1.04933
1.04927
1.04880
1.04874
1.04838
1.04832
1.02417
1.02414
1.02415
1.02412
1 ,02393
1.02390
1.02372
1.02369
509
INDUSTRIAL AND ENGINEERI-VG CHEMISTRY
April, 1927
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INDUSTRIAL ALVDENGINEERING CHEMISTRY
510
table interpolated values can be obtained for any strengt,h of glycerol desired. Table IV-Rate GLYCEROL
Per cent 100 97.5 95 90
so
70 60 50 40 30 20 10
Water
of Expansion4 of Mixtutes of Glycerol and Water CHANGE IN SPECIFIC GRAVITY PER DEGREE
15-200 c .
15-25O C.
20-25' C.
0.000615 0.000620 0.000615 0.000610 0.000620 0.000580 0.000540 0.000485 0.000430 0.000370 0.000300 0.000230 0.000180
0.000615 0.000615 0.000615 0.000615 0.000615 0.000570 0.000545 0.000495 0.000435 0.000385 0.000315 0.000255 0.000205
0.000610 0.000605 0.000615 0.000620 0.000610 0.000565 0.000550 0.000510 0.000445 0.000400 0.000325 0.000280 0.000230
a The term "coefficient of expansion" which has sometimes been used to express this function, has been purposely avoided in order not to confuse it with the true coefficient of expansion which is the change in volume with the temperature.
A Correction
Since reference has frequently been made in the literature to the work of Griin and Wirth7 in establishing the specific gravity of glycerol, it is well to make a correction to the otherwise very excellent work of these investigators. In order to compare the specific gravities found by several authors for 100 per cent glycerol, they reduced these figures all to 15'/15' C. The following results were thus obtained:
VOl. 19, No. 4 STROHMER
GERLACH
17.5'1'17.5' C. 200/200 c. Observed 1.262 1.2620 Calculated to 15D/150C. 1.260 1.2580
NICOL
2 0 ~ / 2 0c. ~ 1.26348 1.2594
In calculating these results to 15"/15' C., however, we find: Strohmer, 1.2630; Gerlach, 1.2639; Nicol, 1.2654. These figures are quite different from those found by Griin and Wirth. It is evident that they have made an error in their calculations, as their results show lower values for 15"/15' C . than those given for the higher temperatures. These authors concluded that the table of Gerlach a t 15'/15' C. was the best, since their own results for 100 per cent glycerol agreed with his. Such a conclusion is not justified, however, as Gerlach appears not to have attempted accuracy in the fourth decimal place except with 100 per cent glycerol. Moreover, Nicol's figure, if correctly calculated, is also in close agreement with theirs. On similar ground, we might conclude that the table of Nicol was the most accurate, as his result is in good agreement with ours for 100 per cent glycerol. However, we find poor agreement for some of the lower percentages, especially 80 per cent. As a matter of fact, Nicol's table appears to be the best that has been published up to the present, although it is of limited usefulness as the temperature 20' C . is one not generally used in determining the specific gravity of glycerol, and even if recalculated to another temperature, the incorrectness of some of its values impairs its usefulness.
Fungicidal and Bactericidal Action of Selenium and Tellurium Compounds' By Norman M. Stover with B. S. Hopkins ENIVERSITY
I
OF
ILLINOIS, URBANA, ILL.
N T H E periodic table, the elements selenium and
tellurium lie between arsenic and antimony on the one side and the halogens on the other. Since all these bordering elements possess toxic properties, it is not surprising that compounds of selenium and tellurium also show considerable toxicity. The purpose of this investigation was to determine the possibility of using compounds of selenium or tellurium as bactericides and fungicides to combat such tree diseases aa pear blight (B. amylovorus), apple blotch (Benturia inaequalis), and chestnut blight (Endothia parasitica), and also as herbicides against such weeds as dandelions, Canada thistle, burdock, plantain, and pigweed. The work of such investigators as Joachimoglu,2 Joachimoglu and Hirose,3 Lehmann,d and Stoklasa5 has shown that selenium dioxide is more toxic than sulfur dioxide, that selenites and tellurites are more toxic than selenates and tellurates, and that selenites are more toxic than tellurites. If the toxic properties of selenium and tellurium compounds are associated with the ease with which such compounds are reduced, then it is not surprising that selenites are more toxic than tellurites, since selenium compounds are in general more readily reduced than the corresponding tellurium compounds. Submitted b y Norman M. Stover to f Received December 2, 1926. the Graduate School of the University of Illinois in partial fulfilment of the requirements for the degree of doctor of philosophy. 4 Biochcm. Z.,107, 300 (1920). 8 I b i d . , la6, 1 (1921). d l b i d . , 134, 390 (1922). 6 Comfit. rend., 174, 1075, 1256 (1922); Biochcm. Z.,130, 604 (1922).
The action of selenium and tellurium compounds on bacteria and fungi has been studied by a large number of investigators. The results of many experiments have shown that various compounds of selenium are reduced by bacteria, the reduced selenium being deposited within the cell, coloring it red, while the medium remains colorless. Corresponding tellurium compounds produce a gray deposit when so reduced. Similarly, Turinas was able to show that both selenium and tellurium are deposited in the tissues of plants by the reduction of selenites, selenates, tellurites, and tellurates. Several workers have reported that such compounds are decidedly injurious to the growth of plants. Lougee? experimented with selenium compounds with a view to using them to control such tree diseases as apple blotch and pear blight, and also as herbicides against dandelions. The authors have undertaken to continue this work by applying selenium and tellurium compounds to still other weeds and to one other tree disease-namely, chestnut blight. Preparation of Materials For the field experiments, approximately 0.1 normal solutions of selenious acid, sodium selenite, and sodium tellurite were made up and served as stock solutions. These were diluted as required to the concentrations to be tried out. Crystals of pure selenious acid were used to make up the solution of selenious acid. Sodium selenite solution was made by dissolving a weighed amount of selenious acid Z., 129, 507 (1922). THISJOURNAL, 17, 456 (1925).
e Biochem. 7
