The pH meter is a common analytical instrument widely used in agriculture, environmental protection and industry. Soil pH is one of the important fundamental properties of soil. Factors such as the temperature and ionic strength of the solution to be measured should be considered during pH measurement. Tips for using a pH meter:
1. Before using the pH meter, pull off the rubber sleeve on the upper end of the electrode to expose the upper hole.
2. The electrode bulb must be kept moist. If it is found to be dry, it should be immersed in 3mol/L potassium chloride solution or weak acid solution for 3 hours before use to reduce the asymmetry of the electrode.
3. Normally, if the pH meter is used continuously, it should be calibrated once a day. There is usually no need to recalibrate the pH electrode within 24 hours.
4. When the pH meter is measuring, the electrode wire of the electrode should be kept still, otherwise the measurement will be unstable.
5. Do not immerse the pH meter electrode in distilled water.
6. The standard solution used for calibration usually uses a pH = 6.86 standard solution for the first zero point calibration, while the second point slope calibration uses a standard solution close to the pH value of the measured solution. If the measured liquid is an acidic solution, the standard solution should choose PH = 4.00, if the measured liquid is an alkaline liquid, then the standard solution should choose PH = 9.18.
7. The pH monitoring value will also change with the temperature, so if you need a high-precision pH value, it is best to equip a temperature-compensated probe.
8. If the test liquid is heavily polluted, the electrodes must be cleaned and activated after use.
9. After measurement, wash the electrode with distilled water, blot dry with filter paper, cover the electrode protection cover, and cover the electrode filling hole.
10. When the pH meter is used frequently, immerse the electrode in a saturated potassium chloride solution to keep the electrode glass bulb moist.
11. During the measurement process of the pH meter, the lead-in wire of the electrode should be kept still, otherwise the measurement will be unstable. The input terminals of the instrument must be kept clean and dry. When the instrument is not in use, please insert the short-circuit plug into the measuring electrode socket to prevent dust and water vapor from entering. When using in a place with high ambient humidity, please dry the electrode plug with a clean gauze.