Configuration method of pH standard buffer solution
The instrument is equipped with three packs of powdered standard buffer when it leaves the factory, and each pack of powdered standard buffer can prepare 250mL of buffer solution. Do not use metal containers for buffer preparation.
Take the preparation of 250mL pH value = 6.86 standard buffer as an example to illustrate the preparation method; (1) When preparing, use a clean plastic (glass) container with a capacity greater than 250mL, take out the plastic pouch of pH = 6.86 (green) buffer, tear it open and put the inside Pour 2 sachets of white powder into the container.
(2) Add 250mL of distilled water to a plastic (glass) container. If distilled water is not available, 250mL of purified water in a commercially available bottle can be used instead.
(3) Use a clean glass or other tools to stir slowly until the powder is completely dissolved.
Prepare 4.0 and 9.18, (7.0 and 10.0) standard buffer method as above. After the preparation of the three standard buffer solutions is completed, labels should be labeled in time to prevent confusion in the future.
Use of Standard Buffers
The 250mL standard buffer solution can be divided into multiple uses. When the instrument is calibrated, three small plastic (glass) containers are used to pour 4.01, 6.86 and 9.18 standard buffer solutions respectively.
And mark it. The amount of standard buffer solution can be used as long as it can completely submerge the glass electrode. The used standard buffer should be discarded and not reused. The remainder is stored in
20-25 ℃ cool and dry place.
