How to correctly use the combination electrode of a pH meter?
⑴There should be no air bubbles at the front end of the bulb. If there are air bubbles, they should be thrown away with force.
⑵ After the electrode is taken out of the soaking bottle, it should be shaken in deionized water and shaken dry. Do not wipe the bulb with paper towels. Otherwise, the electrostatic induction charge will be transferred to the glass film, which will prolong the time for the potential to stabilize. A better way is to use a Rinse the electrode with measuring solution.
⑶After inserting the pH composite electrode into the solution to be measured, stir and shake it for a few times before leaving it still. This will speed up the response of the electrode. Especially when using a plastic shell pH composite electrode, the stirring and shaking should be more vigorous, because there will be a small cavity between the bulb and the plastic shell. After the electrode is immersed in the solution, sometimes the gas in the cavity will not be discharged in time, causing bubbles to form, causing the ball to The bubbles or liquid junctions are in direct contact with the solution, so vigorous stirring and shaking is required to eliminate bubbles.
⑷After testing in viscous samples, the electrode must be rinsed repeatedly with deionized water several times to remove the sample adhered to the glass film. Sometimes it is necessary to wash the sample with other solutions first, then wash away the solvent with water, and then immerse it in the soaking solution for activation.
⑸Avoid contact with strong acids, alkalis or corrosive solutions. If you test such solutions, you should minimize the immersion time and clean them carefully after use.
⑹ Avoid use in dehydrating media such as absolute ethanol and concentrated sulfuric acid, which will damage the hydrated gel layer on the surface of the bulb.
⑺The shell material of the plastic shell pH composite electrode is PPS. If the electrode shell medium is damaged, a glass shell pH composite electrode should be used instead.
