How to use the compound electrode of pH meter correctly?
(1) There should be no air bubbles at the front end of the bulb, if there are any air bubbles, they should be shaken off by force.
(2) After the electrode is removed from the immersion bottle, it should be shaken in deionised water and shaken dry, do not wipe the bulb with a paper towel, otherwise the time of potential stabilisation will be prolonged due to the electrostatic induction of charge transfer to the glass membrane, a better method is to rinse the electrode with the solution under test.
(3) pH composite electrode inserted into the measured solution, to stir and shake a few times before placing it stationary, this will speed up the response of the electrode. Especially when using the plastic shell pH composite electrode, stirring and shaking to be more powerful, because there will be a small cavity between the bulb and the plastic shell, the electrode is immersed in the solution, sometimes the gas in the cavity can not be eliminated in time to produce bubbles, so that the bulb or the liquid interface with the poor contact with the solution, so it must be vigorously stirring and shaking in order to exclude air bubbles.
(4) in the viscous specimen after the test, the electrode must be repeatedly rinsed with deionised water several times to remove the specimen adhering to the glass film. Sometimes it is also necessary to wash off the specimen with other solutions before washing off the solvent with water and immersing it in the immersion solution for activation.
(5) Avoid contact with strong acids and alkalis or corrosive solutions, if testing such solutions, the immersion time should be minimised and carefully cleaned after use.
(6) Avoid use in dehydrating media such as anhydrous ethanol, concentrated sulfuric acid, etc., they will damage the hydrated gel layer on the surface of the bulb temperature compensation on ph meter (acidity meter) measurement.
(7) plastic shell pH composite electrode shell material is PPS, such as damage to the electrode shell medium, at this time should be changed to a glass shell pH composite electrode.
