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tector works with conventional gas chromatography to measure very small quantities of some hydrocarbon in air.
NBS Redetermines Value of the Faraday
Many of the exhibits at the Instrument Society of America's winter InstrumentAutomation Conference and Exhibit were in the main arena of the Sam Houston Coliseum in Houston, Tex.
phasis of the conference program was concentrated on chemical and petroleum processing instrumentation. Systems engineering, instrument maintenance, and pipeline instrumentation sessions were also held. Some of the papers of special analytical interest included those that described use of an ultrasonic viscometer on polymerization, how radiation may be applied to chemical analysis through density and adsorption coefficient measurements, and use of newer detectors available for use with gas chromatographs.
In the field of gas chromatography, J. M. Klaasse and W. Hampton of American Instrument Co. covered the company's new research instrument which permits use of two different columns either singly or in combination, and use of three different detectors— thermistor, tungsten filament, and radio frequency discharge. Use of Golay columns and flame ionization detector in a laboratory unit was discussed in a paper by Richard B. Condon and Philip R. Schallv of Perkin-Elmer Corp. Finally, F. D.' Martin of The Dow Chemical Co. told how a beta-ray de-
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ANALYTICAL CHEMISTRY
A new electrochemical determination of the faraday has been accomplished at the National Bureau of Standards. D. K. Craig and W. J. Hamer, assisted by Catherine Law and J. I. Hoffman, made the new determination by using an electrochemical method which dissolves, rather than deposits, silver in an electrochemical solution. Preliminary values indicate that the faraday is 96516.4 ± 2.0 coulombs per gram equivalent on the physical scale. Earlier values of the faraday had been obtained by depositing silver from a solution of silver nitrate, but errors in the result can occur due to occlusion of part of the solution in the deposited silver, according to NBS. In the Bureau's method, purified silver was used as an anode and dissolved in a solution of perchloric acid by an electric current. The difference in weight of the anode before and after the process was divided by the measured quantity of electricity that had been passed through the coulometric circuit. Thus was obtained the electrochemical equivalent. In the course of the work, the atomic weight of the silver used was determined in an associated experiment, using a mass spectrometer. The value of atomic weight thus derived was found to be 107.8730 ± 0.0015 (chemical scale), representing a 95% confidence interval. NBS says that, although this value differs significantly from the International Table of Atomic Weights value of 107.880, it was nevertheless used in the calculation of the new faraday value.
Eastern Symposium Dates Set Announcement has been made of the dates for the 1960 Eastern Analytical Symposium. The meeting is to be held at the Hotel New Yorker in New York City from November 2 to 4. As in the past, it will be held under sponsorship of the analytical groups of ACS' New York and New Jersey Sections, the Society for Applied Spectroscopy of New York, Delaware Valley, New England, Baltimore, and Washington, and The Metropolitan Microchemical Society. Further information concerning the symposium can be obtained from Edwin A. Wynn, publicity chairman, Fisher Scientific Co., Chemical Manufacturing Division, 1 Reagent Lane, Fair Lawn, N. J.
