In the sample including non-aqueous solvent, the pH value indicated on the pH meter is not simple to use such as that in the aqueous solution. For this reason, note that the pH value measured in the non-aqueous solvent is only an indicator which shows the amount of hydrogen ion activity in the measuring solvent.
When performing a measurement, exercise the caution regarding the following items.
The KCl that leaks from the liquid junction of the reference electrode with the inner solution (KCl solution) does not in general dissolve in most non-aqueous solutions, so that the liquid junction becomes obstructed. (In order to solve this problem, some electrodes utilize lithium acetate (CH3COOLi), which is soluble in organic solvent, as the inner solvent on the outer side of a double-junction construction.)
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