In order to perform pH determinations with a glass electrode, the cell potential was measured for three standard solutions with the following pH values at 25 C: 2.04, 7.05, and 9.20. The cell voltage...

In order to perform pH determinations with a glass electrode, the cell potential was measured for three standard solutions with the following pH values at 25 C: 2.04, 7.05, and 9.20. The cell voltage readout (in mV) for each of the above solutions was 238.0, 37.5 and, 164.5, respectively. Calculate: (a) the sensitivity of the pH sensor; (b) the pH of an unknown sample yielding a cell voltage of 20.5 mV; (c) the pH deviation from the actual value if the sample temperature is 35 C