’THE AMERICAN CHEMICAL SOCIETY. XVI.-PROCEEDINGS. Regular Meeting, April 1, 1880. in the chair. Thirteen members present. Dr. E. R. SQUIBR T h e minutes of the previous meeting were read and approved. I n the absence of a quorum the regular business was deferred. T h e following papers were read. 1. (‘Miscellaneous Chemical Notes,” by T. T. MORRELL.2. On Peroxide of Hydrogen and Ozone ” (second pdper), by Prof.
‘‘
A. R.
1,EEDS.
After wliich the meeting adjourned.
ARTHUR H. ELLIOTT, Recording Secretary. XVII.-MISCELI,ANEOUS CHEMICAL NOTES.
BY T. T. MORRELL. I. ESTIMATION OF SMALL QUANTITIES O F POTASH WITH PLATINIC
CHLORIDE.
When an aqueous solation of platinic chloride is mixed with potassium iodide, there is produced a peculiar red coloration of remarkable intensity, according to the reaction : PtCI, 6KI K,PtI, 4 KCI. Advantage ma) be taken of this rcaction to estimate, colorimetrically, minute quantities of platinum, providing no other subMtance, which produces with tfhe iodide a colored s?lution, is present. If a solution of platinic chloride of known strength is kept on hand, a standard for measuring the color may be formed by mixing a measured quantity with potassium iodide. An excess of pure iodide appears to have no effect upon the intensity of the color. However, it is best to use about the same quantity in the estimation and in the formation of the standard color, allowing five or six minutes to develop the maximum tint, after which the sohitions may be suitably diluted. I t is well, also, to keep the cylinders in which the comparison of color is made, stoppered, t o exclude the air as much as possible.
+
= I
+
T o apply this test ta the estimation of the miall qiiantitiw of potasl. found in lime-stones, clays, etc., the double salt with pl:itinic* chloride is formed, and washed iipon the filter as usual. Tlie filtcr is lint in a warm place, until most of thc alcollol o r ether, iisctl i n \v:idiiiig, has cvaporatetl, when thc precipitate I ~ K LLe~ tlissolv, t l i i i n littl(1 h u t water. The solutioii is now ~‘ooled,and traiiaferrtd t o thca twtiiig cylinder, and iodide is added. t f tlie iotliilc is :idded i i i crystals, it is best to agitate tlie liquid while it is being dissolved, t o pi’eveiit tlle solution a t tlie bottorii of the cylinder fi*om 1)ecoriiing too coiice~itratetl. Instead of estimating colorimetrically, we may, since two equivalents of iodine would be yielded to reducing agents, titrate the soliition with chloride of tiii. For this ~ U ~ I J U Sa ~little , 1iydroch;oric acid is addcd, and the tin solution is r u n i n until the red &lor disappears, and the solutioii is pale ycllow. ‘l‘he end of the reaction is sharply detincd, if the aniount of the platinic salt is not too great. ?‘he atldition of hydrochloric acid deepens the color, but :ilxays in proportion to the platinic salt present. 11. E S T I M A T I O S O F COPI’ER A S O X I D E .
When copper has been precipitated as sulphide, it k sonietirnes ignited with a little tloul’ of sulphur, in a stream of hydrogen, and weighed. I have sometimes resorted to a shorter and equally accurate method, which I do not remember to have seen in print, viz. : that of converting the sulpliide directly into oxide. For this purpose, the sulphide is removcd from the filter, the tilter ash added, and the whole roasted for a short time at a gentle heat. I t is now very carefully heated, several times, with a little nitrate of a~~irnoiiia, by which it is converted into oxide free from every trace of sulphuric acid. If fuming nitric acid is a t hand, the sulphide may be warnied with a few drops, and the resulting mixed oxide and sulphate ignited, two or three times, with a little powdered carbonate of ammonia, and weighed. This is easier of execution than the ignition with nitrate of ammonia, as the latter is apt to deflagrate, if the heat is not very carefully applied. 111. COMPOSlTIOS O F T H E GASES I N T I l E CAVITIES O F A B E S S E M E R
JSGOT.
I n December, 1876, I made an analysis of the gases contained in the “ blow-holes” of a Bessemer ingot. T h e ingot was “ bottom cast,” eight ingot moulds being simultaneously filled from a central
ON PEROXIDE OF HYDROQEN A N D OZONE.
147
sprue, down which considerable air was carried along with the metal. The reeult of the analysis leaves little doubt that the bottom, made of red bricks and fire-clay, was not thoroughly dry. The gases were collected over water, the ingot being immersed in an iron box, with a drill passing through a packing box into its side. The boring wae done as rapidly as possible. This method of collecting the gases is riot free from objections, but was the best at command. The average of two closely accordant analyses was as follows : Carbonic oxide. ................. 2.08 Hydrogen.. .56.42 Nitrogen .39.86 Oxygen ....................... 2.14
................... .....................
A few of the cavities near the surface evidently communicated with the air, hence a little free oxygen, and a larger percentage of nitrogen. The specific gravity of the solid steel, about one foot from the top of the ingot, was 7.866.
xvII~.-oN P E R O X I D E
OF
BY ALBERTR.
HYDROGEN AND
LEEDR,
OZONE.
PxD.
[Second Paper.] (With Figures on Plate I.) Read April Ist, I.-UPON
1880.
T H E R E L A T I V E A M O U N T S O F P E R O X I D E OF H Y D R O G E N A N D
OZONE, O B T A I N E D I N T H E OZONATION
PHORUS, AS D E T E R M I N E D
O F A I R B Y MOIST P H O S -
BY T H E METHOD
O F DECOMPOSITION
O F T H E S E BODIES, THROUGH T H E A G E N C Y O F H E A T .
I n preceding articles, and more especialty in the first paper with the above title, it has been pointed out that both hydrogen peroxide ;md ozone are formed by the action of air upon moist phosphorus, Moreover, a number of experiments, protracted for several months (in which as many as 481 liters of purified air were used in a single experiment, and every devisable precaution was employed), were brought forward in support of the proposition that the percentage o f hydrogen peroxide in the ozonised air bears a constant ratio to t h a f of the ozotze. The conclusioii drawn from these results was, that the production of hydrogen peroxide, like that of ammonium nitrate, depends upon the same series of chemical changes as those which are
