October 15, 1932
INDUSTRIAL
AND E N G I N E E R I N G CHEMISTRY
strong sodium hydroxide solution and boiling until the vapors ceased to affect litmus paper. The calcium ion in excess from the calcium fluoride precipitation, which partially precipitated as hydroxide, was removed by filtration, the solution transferred to a volumetric flask, and aliquot portions titrated by the standard method, using mannitol ( 5 ) . Good results were also obtained for boron. The experimental procedure as finally decided upon was as follows: Approximately half-gram samples were accurately weighed in No. 00 gelatin capsules and placed in the cup of a Parr sulfur bomb of the electrical ignition type, together with a fusion mixture of 10 grams of sodium peroxide, one gram of potassium chlorate, and 0.5 gram of sugar. The bomb was tightly closed, well shaken, and shorted with direct or alternating current of about 20 volts and 8 amperes. For the fusion wire, standard iron wire “for analysis” was used in order not to introduce additional impurities. The bomb was permitted to become quite hot, and then immersed in cool water until it could be handled. The cup was then removed, and the contents dissolved out by placing it on its side in a 400-cc. beaker, covering it with water, and warming gentli. After boiling for a few minutes to coagulate the heavy metallic hydroxides from the cup and the fusion wire, the solution was filtered. Fifteen grams of ammonium chloride were roughly weighed and introduced into the solution, which was boiled until the odor of ammonia no longer persisted (one to two hours). If a new precipitate formed during the boiling, it was filtered out before proceeding. To the hot solution, 10 cc. of a 2 N solution of calcium nitrate were added drop by drop, with stirring. This provided a large excess of calcium ion to depress the solubility of the precipitate. A filter accelerator was dropped in and macerated well, and the boiling was continued for a few minutes. Occasionally it was necessary to add one cc. of approximately 3 N ammonium hydroxide to assist in coagulatc ing the precipitate. The solution was cooled in running water until cold, and filtered, using strong suction and a platinum filter cone. The filtrate was reserved for the boron analysis. The volume of wash-water should not exceed 50 cc. The paper containing the precipitate was dried a t 110” C. and ignited to constant weight in a platinum crucible over a Fisher burner. To the filtrate was added sufficient 4 N sodium hydroxide to produce a precipitate of calcium hydroxide and carbonate. The solution was then boiled until the vapors
393
no longer affected red litmus paper, and filtered into a 250-cc. volumetric flask. After being diluted to the mark and mixed thoroughly by shaking, a 50-cc. portion was withdrawn. This was titrated to neutrality with methyl orange, using 0.1 N hydrochloric acid. The remainder of the solution was neutralized with an equivalent amount of hydrochloric acid, but no methyl orange was added. The necessary amount of mannitol was added, together with a few drops of phenolphthalein, and the solution titrated to the first faint tinge of pink with 0.1 N sodium hydroxide solution (carbonatefree). The buret reading was calculated to boron. Using this procedure, the following results were obtained: ALIQUOT
QAafPm
Gram
NaOH SOLUTION Amt. B B used FOUND CALCD.
F F PART NorCaFz FOUND CALCD.TITRATED mality Gram % ’ % METHYL ACETATE B O R O N TRIFLUORIDE
0.5398 0.4446 40.12 40.19 0.5057 0,3716 o:iioo 40:i4 40:i9 0.5861
....
...
...
iji
o:iiis o:iiis
476
Cc.
%
%
(CBSCOOCBx:BB8) 2i:is 2i:io
i:io i:ii
i:ii7
+:ii7
ETHYL ACETATE BORON TRIFLUORIDE (CHSCOOCZHS:RFS)
MONOAMMONO B O R O NTRIFLUORIDE
0.2540 0.2976
0.3510 67.32 67.18 0,4106 67.20 67.18
:$:
(NHSBF~
0.1258 18.90 12.66 12.75 0.1268 22.30 12.75 12.75
These compounds were freshly made and purified by crystallization or distillation immediately before the analysis. The three are all solids, easy to obtain in a pure condition, and were chosen for that reason. LITERATURE CITED (1) Bowlus and Nieuwland, J. Am. Chem. SOC.,53, 3835 (1931). (2) Carrikre and Rouanet, Compt. rend., 189, 1281 (1929). (3) Clarke and Bradshav, AnuZUst, 57, 138 (1932). (4) Kraus and Brown, J. Am. Chem. SOC.,51, 2690 (1929). (5) Mahin, “Quantitative Analysis,” p. 205, McGraw-Hill, 1924. (6) Marignac, Chem. Cent., 39, 490 (1863). (7) Mellor, “Inorganic and Theoretical Chemistry,” p. 125, Longmans, 1924. (8) Mougnaud, Compt. rend., 194, 1507 (1932). (9) Rose, Ann., 72, 343 (1849). (10) Vaughn and Nieuwland, IND. EXQ.CHEM.,Anal. Ed., 3, 274 (1931).
RECEIVED June 3, 1932. From a thesis submitted by Daniel J. Pflaum to the Graduate School of the University of Notre Dame in partial fulfilment of-the requirements for the degree of master of science.
A Gas Buret for Catalase Apparatus DEANA. PACK,The Birdseye Laboratories, Gloucester, Mass.
T
HE buret described is believed to be of some general service as well as being an improvement for the catalase apparatus devised by Appleman (1). This buret was constructed so as to be placed in the water bath for maintaining n constant temperature for the gas to be measured. The apparatus consists of a short length of buret, a parallel reservoir tube, a siphon which allows the leveling bottle to be operated from without the bath, and connections for the reaction bottle and the outlet. The lower ends of the buret, B, and reservoir tube, R, are drawn out into tube, S, which serves as the apparatus support and forms one arm of the siphon connecting with the leveling bottle. The upper ends of B and R are drawn out into tube A , which connects with the reaction bottle. Tube A is also provided with an outlet tube, C. The buret with its reservoir tube is calibrated in
A’
centimeters for the readings on the buret. This apparatus permits all the chambers containing gas to be submerged in water. It must be kept in mind that as the buret is shortened and the volume of the r e s e r v o i r is increased, the errors of reading are increased in proportion. This arrangement has been in service for one year with good results. LITERATURE CITED (1) Appleman, C. O., Bot. Guz., 50, 182-92 (1910).
R E C Z I V ~August D 2, 1932.
