| 摘要 |
PROBLEM TO BE SOLVED: To obtain a method in which inaccuracies in conventional measurement of the pH value of a solution to be inspected by a pH meter are excluded, and in which the pH value can be measured precisely, even in the case of a solution to be inspected, which easily influences the display of a pH meter especially for a dissolved solution or the like. SOLUTION: Respective electrodes of a plurality of pH meters for pH measurement, whose display pH values are calibrated by a standard solution having a known pH value, are immersed in a solution to be inspected. Two or more pH meters which are maintained within a prescribed error range are verified as acceptable meters. The acceptable meters are guaranteed as pH meters, which can display a nearly precise pH value under the same conditions as when the solution to be inspected is measured. One among them is used to measure the pH value of the solution to be inspected, and an other is used for reference. The former is immersed in the solution to be inspected so as to measure its pH value continuously, and the latter is immersed intermittently in the solution to be inspected. The pH value of the solution to be inspected is measured by both pH meters. When pH values by both methods agree, it can be recognized that the display of the pH value by the former is precise. |
