Use and Maintenance of pH Meter Electrodes
When the composite electrode is not in use, it can be fully immersed in a 3M potassium chloride solution. Do not soak with detergent or other absorbent reagents.
2. Before use, check the bulb on the front end of the glass electrode. Under normal circumstances, the electrode should be transparent and free from cracks; The bulb should be filled with solution and no bubbles should exist.
When measuring solutions with high concentrations, try to shorten the measurement time as much as possible, and carefully clean them after use to prevent the measured solution from adhering to the electrode and contaminating it.
4. After cleaning the electrode, do not use filter paper to wipe the glass film. Instead, use filter paper to absorb and dry it to avoid damaging the glass film, preventing cross contamination, and affecting measurement accuracy.
5. During measurement, pay attention to the silver silver chloride internal reference electrode of the electrode, which should be immersed in the chloride buffer solution inside the bulb to avoid digital jumping in the display part of the electrometer. When using, be careful to gently shake the electrode a few times.
6. Electrodes should not be used in strong acids, alkalis, or other corrosive solutions.
7. It is strictly prohibited to use in dehydrating media such as anhydrous ethanol, potassium dichromate, etc.
Preparation and preservation of pH standard buffer solution
1. pH reference materials should be stored in a dry place. For example, mixed phosphate pH reference materials may undergo deliquescence when the air humidity is high. Once deliquescence occurs, pH reference materials cannot be used.
2. The preparation of pH standard solution should use secondary distilled water or deionized water. If it is used for measuring pH with a 0.1 level pH meter, ordinary distilled water can be used.
3. When preparing a pH standard solution, a smaller beaker should be used to dilute it to reduce the amount of pH standard solution adhering to the beaker wall. Plastic bags or other containers for storing pH standard substances should not only be emptied clean, but also be rinsed multiple times with distilled water, and then poured into the prepared pH standard solution to ensure the accuracy of the prepared pH standard solution.
4. The prepared standard buffer solution can generally be stored for 2-3 months. If turbidity, mold, or precipitation are found, it cannot be used again.
5. The alkaline standard solution should be sealed and stored in a polyethylene bottle. Prevent carbon dioxide from entering the standard solution to form carbonic acid and reduce its pH value.
