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USGS · 70010358

An automated procedure for the simultaneous determination of specific conductance and pH in natural water samples

D. E. Eradmann·Howard E. Taylor
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Abstract

An automated, continuous-flow system is utilized to determine specific conductance and pH simultaneously in natural waters. A direct electrometric procedure is used to determine values in the range pH 4–9. The specific conductance measurements are made with an electronically modified, commercially available conductivity meter interfaced to a separate module containing the readout control devices and printer. The system is designed to switch ranges automatically to accommodate optimum analysis of widely varying conductances ranging from a few μmhos cm -1 to 15,000 μmho cm -1 . Thirty samples per hour can be analyzed. Comparison of manual and automated procedures for 40 samples showed that the average differences were 1.3% for specific conductance and 0.07 units for pH. The relative standard deviation for 25 replicate values for each of five samples was significantly less than 1% for the specific conductance determination; the standard deviation for the pH determination was ⩽ 0.06 pH units.

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BibTeXRIS

D. E. Eradmann, Howard E. Taylor. 1978. An automated procedure for the simultaneous determination of specific conductance and pH in natural water samples. https://doi.org/10.1016/s0003-2670(01)83567-4

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