How the pH meter needs to be calibrated is actually the best. What is the third point correction of the pH meter depends on your sample situation? As you said, there are many kinds of calibration solutions from pH 1.68 to 12.46, depending on the final pH range of the sample. Use a suitable calibration solution. Our common use is 4.00, 6.86, 9.18. If your sample is more basic, you need 9.18, 10.01, and 12.46.
The order of calibration varies according to the conditions of different instruments. Some requests are calibrated in order, others are not required, and the instrument will be automatically identified. Refer to the instruction manual of the relevant instrument.
Regardless of the pH meter, pH=7 must be corrected, and at the point of correction at two or more days, pH=7 should be corrected.
Two points are generally sufficient to meet the requirements. If the requirements are high, the third point is considered. Some instruments can correct three points, there are modes available, you can use this mode directly. Some who do not have, usually adopt two-point two-point proofreading, that is proofread twice.
Configure these calibration reagents as follows:
1. pH4.00 solution: 10.12 g of potassium hydrogen stannous hydrogenate was dissolved in 1000 ml of high purity deionized water.
2. pH6.86 solution: using potassium dihydrogen phosphate 3.387 g, GR disodium hydrogen 3.533 g, and the solution in 1000 ml of high purity deionized water.
3. pH 9.18 solution: 3.80 g of GR borax was dissolved in 1000 ml of high-purity deionized water.
Note: The water used to prepare the 2 and 3 solutions should be boiled (15-30 min) beforehand to remove the dissolved carbon dioxide. Avoid contact with air during the cooling process to prevent carbon dioxide pollution.
PVC PE Plastic Pulverizer
1. Vertical driving Structure is adopted for high efficiency;
2. Main gear and pinion shaft adopt the carbonizing quenching with high accuracy; smooth driving, low noise and long service life;
Plastic Pipe Production LinePVC PE Plastic Pulverizer,PVC PE Plastic Pulverizer
Zhangjiagang Huade Machinery Technology Co.,Ltd , https://www.tophdextruder.com