The Quality of Platinum - Industrial & Engineering Chemistry (ACS

May 1, 2002 - Ind. Eng. Chem. , 1910, 2 (12), pp 497–497. DOI: 10.1021/ie50024a001. Publication Date: December 1910. ACS Legacy Archive. Note: In li...
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T H E JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY ~

VOL.

DECEMBER, 1910.

11.

No.

12

T H EJ O U R N A L O F I N D U S T R I Ainum L ware developed a white layer on exposure t o high temperatures ; other pieces developed cracks A N D E N G I N E E R I NCGH E M I S T Rwhen Y heated; other pieces gave up several milligrams PUBLISHED BY

T H E AMERICAN CHEMICAL SOCIETY. BOARD OF EDITORS. Editor: W. D. Richardson.

Associate Edilors: Geo. P. Adamson, E. G. Bailey, G. E. Barton, Wm. Brady, Wm. Campbell, F. B. Carpenter, Virgil Coblentz, Francis I. Dupont, W. C. Ebaugh, Wm. C. Geer, W.F. Hillebrand, W. D. Horne, L. P. Kinnicutt, Karl Langenbeck, A . D. Little, P. C. McIlhiney, E. B. McCready, W m . McMurtrie, J. Merritt Matthews, T. J. Parker, J. D. Pennock, Geo. C. Stone, F. W. T r a p h a g e n , E r n s t Twitchell, Robt. Wahl, W m . H. Walker, M . C. Whitaker, 1%'. R . Whitney.

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Published monthly. Subscription price to non-members of the American Chemical Society $6 00 yearly. _ _ _ _ _ ~ ~ -

VOl.

11.

DECEMBER, 19 10.

No. 12

EDITORIALS. T H E QUALITY O F PLATINUM.

Ix recent years there have been many complaints about the quality of the platinum ware used in the chemical laboratory. It has been said that platinum ware of the present day is not as good as that manufactured some years ago. Very recently several large lots of platinum dishes and crucibles have been returned to the makers on account of alleged inferiority, by diffefent Bureaus of the United States Government. Platinum is of fundamental importance in analytical chemical work. I n spite of the substitution of silica ware and apparatus for platinum for certain purposes, the metal remains indispensable for many chemical operations. But it should be pure. If pure, durable platinum ware could be manufactured in former years, there is no reason why as good or better ware cannot be made to-day. 1tTithimproved gas and electric furnaces, and a variety of means for obtaining and controlling high temperatures, the working of platinum should be easier today than ever before; methods of chemical analysis have also been improved even if methods of chemical purification have not to any great extent. The chief complaints which have been made would seem t o indicate gross carelessnesk or lack of skill in manufacture, for it is said, for example, that certain plat-

of iron when digested with hydrochloric acid. All platinum ware is expected by the chemist to withstand certain simple tests. It should not change color, lose,weight, develop cracks, or show a whitish coating after being heated to a high temperature for several hours in the blast flame or furnace. It should not be brittle and should be durable. It should show only an insignificant loss in weight when digested with hydrochloric acid. It is to be hoped that the reported inferiority of some of the modern platinum ware will speedily be corrected. This would be to the best interest of the manufacturers. Poor platinum ware inevitably leads the chemist to look for substitutes-in some cases successfully. It is said that the Bureau of Standards a t Washington has contemplated for some time a n investigation of the whole subject of the quality of platinum apparatus and ware. It would be well if the manufacturers would lend their cooperation in this work. That the results of such a n investigation would be of the greatest interest to the chemical profession does not require emphasis.

T H E PRICE O F POTASSIUM SALTS.

ACCORDING to the calculations of Dr. F. W. Clarke, potassium ranks seventh in point of abundance among the elements composing the chemically-known earth. The elements and their relative abundance down to and including magnesium are: Oxygen, 49.78 per cent.; silicon, 2 6 . 0 8 per cent.; aluminum, 7 . 3 4 per cent.; iron, 4 . I I per cent.; calcium, 3 . 1 9 per cent.; sodium, 2.33 per cent.; potassium, 2 . 2 8 per cent.; magnesium, 2 . 2 4 per cent. I n commerce the greatest outlet for potassium is in the fertilizer trade. Of the ten or twelve elements which enter into the composition of the higher plants and which are necessary for their growth, potassium occupies an important place. Without potassium in the form of soluble salts the higher plants cannot grow and develop to maturity. And, unfortunately, it is one of the elements in which soils are likely to be deficient in available condition. Therefore i t is necessary to apply potash salts to the soils as fertilizers and the use of potash salts for this purpose is increasing a t a n enormous rate. Potassium is found in insoluble condition in the feldspathic rocks and others, and in