TDS, CF, EC, PPM Conversion
First of all: In Germany, 0.1 mS/m at 25°C = 0.425 mg/l TDS (mg/l salinity) used to be used as an approximate value for the conversion. According to Grohmann (somewhat imprecise): µS/cm = 5.48 + 1.43 * TDS. The conductivity of an aqueous electrolyte solution (acids, bases and salts are considered electrolytes) is calculated from the sum of the equivalent conductivities of all dissolved ions, multiplied by their respective concentrations. And: The equivalent conductivity depends on the concentrat...
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