PASCO EZ-2341 Dissolved CO2 ezSample Field Titrator - Manual (Page 2)

2
012-10115
Test Method Description
The dissolved CO
2
ezSample test method employs the a caustic titrant with pH indicator method. 1,2 Results
are expressed in ppm (mg/L) carbon dioxide as CO
2
.
Procedure in the event of sulfide concentrations > 0.4 ppm:
Sulfide will not interfere up to 0.4 ppm. However if the sulfide concentration is > 0.4 ppm, the
following formula is used to calculate the volume of A-1905 Neutralizer Solution that should be added
to 20 mL of the sample prior to performing the Test Procedure:
mL of A-1905 Solution = ppm sulfide ÷ 10 .
NOTE: Because the ampoules have nonlinear scales, the accuracy of the ezSample field titrator kit varies with the analyte
concentration. At the low end of the test range, the accuracy is
± 5%. At the high end of the range, the accuracy falls to ± 20%.
References
1. Method 4500—CO
2
C. APHA Standard Methods, 20th ed., p. 4-31, (1998).
2 Total and Dissolved Carbon Dioxide In Water, Test Method E. ASTM D. 513-82.