V O L U M E 24, NO. 2, F E B R U A R Y
1952
19 A
Sargent
CHEMICAL
Model V
OSCILLOMETER
A very sensitive, stable measuring instrument for chemical analytical procedures, based on the electrical properties of the substances to be identified, differentiated or determined. Opens a new broad field for the development of analytical methods and control procedures. Readings are made in scale units having the dimensions of capacitance, and are proportional to that capacitance which is equivalent to the effect of the sample on the LC ratio of an oscillator. In its measurement of characteristics, it recognizes resistivity, electrical moments of the molecule and all factors contributing to the dielectric constant. Unlike prior electrometric instruments for chemical purposes, the Oscillometer operates with the samples isolated in glass cells, having no structural connection of any kind •with electrical circuits, and so precludes any possibility of electrolytic alteration of sample composition and of contamination by diffusion effects or metallic solubilities. In terms of dielectric constant as applied to the measurement of non-aqueous substances, the sensitivity and reproducibility of the Sargent Chemical Oscillometer averages about 1/300 (one three-hundredth) of a dielectric constant unit, when using full range cells. Stated other-
SARGENT
wise, the range of dielectric measurement from air to water corresponds with a scale range in the oscillometer of roughly twenty-four thousand units, reproduceable within approximately one such scale unit, insofar as instrumental characteristics are concerned. In application to electrolytes, as in titrations normally considered conductimetric or potentiometric, the sensitivity of end point indication is best in the lower range of common conductivities but is excellent in reactions of strong acids and bases as well, provided the reaction medium can be held to a maximum concentration in the order of magnitude of 1/100 normal. The detection of water in non-aqueous media is extremely sharp and indicates direct procedures in many instances. Total working scale range is thirty-two thousand scale units, applied by a multiple-turn dial and additive range switches. Internal range checking standards are incorporated. The frequency is five megacycles. Estimated inherent instrumental precision, 1/10%. Small and large cells are supplied, one for samples from 5 to 12 ml and the other for titrations. The titration cell accommodates a glass stirrer operating continuously without prejudice to the accuracy of measurements. S - 2 9 1 8 0 S A R G E N T CHEMICAL OSCILLOMETER, •with two interchangeable cell holders and cells. Available for prompt delivery $650.00
SCIENTIFIC LABORATORY INSTRUMENTS · APPARATUS · CHEMICALS E. H. SARGENT & COMPANY, 4647 W. FOSTER AVE., CHICAGO 30, ILLINOIS MICHIGAN
DIVISION, 1959
SOUTHWESTERN
EAST J E F F E R S O N
DIVISION,
5915
PEELER
STREET, D E T R O I T STREET,
7,
DALLAS
MICHIGAN 9,
TEXAS
