What happens if we combine a measuring electrode with 3.3 mol KCl electrolyte with a reference electrode with 1 mol KCl in a pH sensor or vice versa?

The reference potential difference between 1 molar and 3.3 molar is approximately 30 mV. The sensitivity of a pH sensor at reference temperature is 59mV/pH. So if you combine a measuring cell filled with 3.3mol KCl with a reference cell with 1mol KCl, then you will have an offset (asymmetry potential) approximately 30/59mV = 0.5 pH. This unbalance will be solved when the sensor is calibrated and it will show itself as Asymmetry Potential. Therefore, as long as the sensor is calibrated properly this should not affect the accuracy of your pH measurement.

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