Kako pravilno shranjevati in uporabljati pH puferske raztopine?
After preparing the buffer solution, it should be placed in a glass bottle or a polyethylene bottle (alkaline pH buffer solutions such as pH 9.18, pH 10.01, pH 12.46, etc. should be placed in polyethylene bottles). The bottle cap should be tightly closed and stored at low temperature (5-10 ℃) in the refrigerator. It can generally be used for about six months. If turbidity, mold or precipitation are found, it cannot be continued to be used. When using, prepare several 50mL polyethylene small bottles, pour the buffer solution from the large bottles into the small bottles, and let them stand at ambient temperature for 1-2 hours until the temperature is balanced before use. After use, it should not be poured into the large bottle to avoid contamination. The buffer solution in the bottle can be used for 2-3 days under environmental conditions of>10 stopinj. Na splošno lahko raztopine s pH 7,00, pH 6,86 in pH 14,00 uporabljate dlje časa. Raztopine s pH 9,18 in pH 10,01 so nagnjene k spremembam pH zaradi absorpcije ogljikovega dioksida iz zraka.
Kakšen je namen pH pufrske raztopine?
Pred merjenjem pH umerite pH meter.
Če želite preveriti natančnost pH-metra, na primer po kalibraciji pH-metra s pH 6,86 in pH 14,00 vstavite pH elektrodo v raztopino pH 9,18 in preverite, ali je vrednost na zaslonu instrumenta skladna z vrednostjo pH standardne raztopine.
Ali je med splošnim natančnim merjenjem potrebno ponovno umeriti pH meter? Po kalibraciji in uporabi pH-metra lahko pride do premika ali sprememb. Zato pred testiranjem vstavite elektrodo v standardno pufersko raztopino, ki je blizu izmerjeni raztopini, in na podlagi velikosti napake ugotovite, ali je potrebna ponovna kalibracija.
