Potentiometric Monitoring of H+
To use potentiometric (e.m.f.) measurements in monitoring the concentration in place of readings, one can trivially set and apply the same equations as above, where is the offset correction, and is a slope correction (1/59.2 pH units/mV at 25°C), such that replaces .
Thus, as before for a titration of strong acid by strong base,
- a plot of vs. will have a linear region before equivalence, with slope
- and a plot of vs. will have a linear region after equivalence, with slope
- both plots will have as intercept and, as before, the acid-side equivalence volume can be used to standardize whichever concentration is unknown, and the difference between acid-side and base-side equivalence volumes can be used to estimate the carbonate content
Analogous plots can be drawn using data from a titration of base by acid.
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