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appearance of t h e 1955 edition " R e a g e n t Chemicals" ( A M E R I -
C H E M I C A L S O C I E T Y Specifications)
reminds us t o say a word a b o u t t h e aims a n d reasons for continued publication of such a book. As every analytical chemist knows, whether dealing with physical or chemical methods, he is constantly concerned with t h e quality of reagents a n d prim a r y or secondary s t a n d a r d s . For m o s t analytical work t h e reagents t h a t can be purchased are of uniform q u a l i t y a n d of such p u r i t y t h a t further purification is unnecessary. M a x i m u m impurities are listed on t h e label, with t h e s t a t e m e n t t h a t t h e reagent meets or m a y be better t h a n A C S specifications. T o realize t h a t early analytical chemists faced a very serious problem a n d t h a t its solution h a s t a k e n years t o achieve, one h a s only t o read excerpts from t h e preface of t h e 1950 edition. As a result of comments regarding the quality of reagent chemicals, t h e Council of
the
AMERICAN CHEMICAL SOCIETY
in
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local section of the AMERICAN CHEMICAL
SOCIETY requested the Council of the Society to take steps t o learn just t h e extent to which a manufacturer or dealer might be held accountable for erroneous statements on labels. T h e communication cited an instance of serious embarrassment to a member of the section who had naively trusted a grossly inaccurate statement as to the amount of an impurity in a reagent chemical. I n January 1917 a 2 8, N O . 3, M A R C H
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1903 appointed a Committee on t h e Purity of Chemical Reagents consisting of John H. Long, chairman; W. F . Hillebrand, secretary; Charles Baskerville, L. M. Dennis, and H. P . Talbot. The committee held one meeting and outlined a program of preparation of specifications. Although no publication of specifications was produced, the committee did exert influence towards better quality of reagents and a decrease in instances of discrepancies between labels and contents of packages of reagent chemicals. Analysts continued t o be disturbed about t h e quality of reagent chemicals on the market. Dr. Hillebrand referred t o the problem in his Chandler Foundation Lecture at Columbia University, November 27, 1916 ["Our Analytical Chemistry and I t s F u t u r e , " J. Ind. Eng. C'hem., 9, 170 (1917)]. He emphasized the need for concerted action by chemists to raise the standards of quality and reliability of available reagent chemicals. I n 1916 a
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Committee on Analyzed Reagents was appointed, consisting of W. F . Hillebrand, chairman, Charles Baskerville, and W. D . Bigelow. This committee's report to the council meeting in April 1917 proposed t h a t an effort be made to obtain the appropriation by Congress of funds to enable t h e National Bureau of Standards to purchase reagents on the open market and publish results of analyses of the samples along with the analyses on the labels. The committee report recommended the appointment of a permanent committee of the Society to act in an advisory capacity to the Bureau of Standards and the manufacturers of reagents. T h e committee appointed consisted of W. D . Bigelow, chairman, Charles Baskerville, and C. C. McDonnell. T h e appropriation for work b y the Bureau of Standards was not obtained. At the meeting of the Council of t h e AMERICAN
CHEMICAL
SOCIETY
in
April
1919 the subject of apparatus was added to the field of work of the committee. In August 1921 the committee published specifications for hydrochloric, nitric, and sulfuric acids and ammonium hydroxide in about the style that has been followed in the later publications of specifications by the committee. In accordance with a recommendation in the committee report for 1924, the committee was divided into two committees and some new members were added to the Committee on Guaranteed Reagents. The present collection of specifications may be considered a summary of t h e work on reagents done by the committee under different names since the original appointment in 1917 of the Committee on Analyzed Reagents. However, the present set of specifications was started in 1925 and is the product of those holding membership in the committee from that time. W. D . Collins, of t h e Geological Survey, now retired, served as chairman from 1925 t o 1942; E d w a r d Wichers, of t h e B u r e a u of S t a n d a r d s , served t h r o u g h 1955. W . Stanley C l a b a u g h , also of t h e B u r e a u of S t a n d a r d s , is prese n t chairman. T h e 1955 edition included t h e 1953 appendix published in ANALYTICAL C H E M I S T R Y .
The commit-
tee's effort h a s gone t o revision of existing specifications r a t h e r t h a n develo p m e n t of new ones. While t h e committee recognized t h a t it m u s t a d d new reagents, its first obligation is t o keep up to d a t e t h e present list of those in common use. T h e committee welcomes suggestions from manufacturers or users of chemicals. T h e research analyst who is developing special methods, especially in t h e i m p o r t a n t field of traces, m u s t continue t o be vigilant in his selection of reagents and, if necessary, purify reagents t h a t do n o t meet his specifications. H e is more fortunate t h a n earlier workers, in t h a t he h a s reagent grade to s t a r t with a n d t h e specifications a n d m e t h o d s of t e s t are available for his guidance. I t is encouraging t h a t in this c o u n t r y a n d abroad m a n u f a c t u r e r s of both inorganic a n d organic compounds are concerned n o t only with high grade reagents b u t with chemicals of sufficient p u r i t y to serve as s t a n d a r d s .
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