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If using a meter with direct concentration readout capability
See individual meter instruction manuals for more specific
information.
1. Measure 50 mL of the more dilute standard into a 150 mL
beaker. Add 5 mL carbon dioxide buffer. Stir thoroughly.
2. Rinse electrodes with distilled water, blot dry and place into the
beaker. Wait for a stable reading, then adjust the meter to
display the value of the standard as described in the meter
instruction manual.
3. Measure 50 mL of the more concentrated standard into a
second 150 mL beaker. Add 5 mL carbon dioxide buffer.
Stir thoroughly.
4. Rinse electrodes with distilled water, blot dry and place into the
beaker with more concentrated standard. Wait for a stable read
ing, then adjust the meter to display the value of the second
standard, as described in the meter instruction manual.
5. Measure 50 mL of the sample into a 150 mL beaker. Add 5 mL
carbon dioxide buffer. Stir thoroughly. Rinse electrodes with
distilled water, blot dry and place into sample. The concentration
will be displayed on the meter.
