Merck uses Wenner Potentiometer in measuring molecular measuring molecular weights ... weights of vitamins, hormones, antibiotics, and other organic substances bythe exacting boiling

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  • Scientist in Merck & Co.'s Research and Develop- conjunction with use of Wenner Potentiometerment Division is watching galvanometer scale in in measurement of molecular weight.

    Merck uses Wenner Potentiometerin measuring molecular weights

    Merck & Co. chemists determine molecularweights of vitamins, hormones, antibiotics, andother organic substances by the exacting "boilingpoint elevation method". Precision of this deter-mination depends upon the accuracy with whichminute temperature differences can be measured.To obtain the ultimate in precision, therefore, theMerck laboratory uses a Wenner thermocouplepotentiometer. With this instrument Merck re-searchers obtain temperature difference measure-ments consistent to within 4-0.0002 C.

    The Wenner Potentiometer is the ideal instru-ment for making these highly precise measurementsof minute voltage. On its low range the instrumentis calibrated from 0 to 11,111 microvolts, in stepsof 0.1 microvolt, and has a limit of error of only4(0.01%7 + 0.1 microvolt).For a description of the instrument, see Cat.

    EH22-33A(1). Write Leeds & Northrup Co., 4926Stenton Ave., Phila. 44, Pa.

    - SUtING INSTRUMENTS TELEMETERS AUTOMATIC CONTROLS HEAT-TREATINC rURNACES

    Jrl. Ad EH22-33A-242(la)

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