Dab tsi yog pH standard buffer tov? Nws cov yam ntxwv yog dab tsi?
1. Dab tsi yog pH standard buffer tov? Nws cov yam ntxwv yog dab tsi?
Cov tshuaj pH tsis yog cov tshuaj uas tuaj yeem tswj tau tus nqi pH ruaj khov. Yog hais tias ib qho me me ntawm cov kua qaub los yog cov hauv paus ntxiv rau cov tshuaj no, los yog cov tshuaj tiv thaiv hauv cov tshuaj ua rau me me ntawm cov kua qaub los yog cov hauv paus, thiab cov tshuaj yog diluted tsim nyog, pH tus nqi ntawm cov tshuaj yog qhov ruaj khov thiab tsis hloov. Cov tshuaj no tuaj yeem tiv taus me me ntawm cov kua qaub lossis cov hauv paus lossis loj lossis me me dilution, thiab ua kom tus nqi pH tsis hloov pauv yog hu ua cov tshuaj tsis haum.
Tus qauv pH tsis muaj cov yam ntxwv hauv qab no:
(1) Tus nqi pH ntawm Standard tov yog paub thiab ncav cuag qhov tseeb;
(2) Tus nqi pH ntawm Standard tov muaj zoo reproducibility thiab stability, loj tsis muaj peev xwm, me me dilution nqi thiab me me kub coefficient;
(3) Txoj kev npaj ntawm kev daws yog yooj yim;
Yuav ua li cas npaj pH txheem tsis tov?
Rau kev ntsuas pH dav dav, ib txheej ntawm pH muaj pes tsawg leeg reagents (muaj peev xwm npaj 250mL) tuaj yeem siv. Thaum npaj cov tshuaj, cov dej deionized yuav tsum tau siv thiab ua ntej boiled rau 15-30 feeb kom tshem tawm cov carbon dioxide yaj. Txiav lub hnab yas, ncuav cov reagent rau hauv lub beaker, yaj nws nrog tus nqi tsim nyog ntawm deionized dej, yaug lub hnab ntim, ncuav rau hauv 250mL volumetric hwj, dilute nws mus rau lub teev, thiab co nws zoo.
3. Yuav ua li cas khaws thiab siv cov tshuaj pH tsis zoo?
After preparing the buffer solution, it should be packed in a glass or polyethylene bottle (alkaline pH buffer solution, such as pH=9.18, pH=10.01, pH=12.46, etc., should be packed in a polyethylene bottle) with a tight lid. It should be stored in a refrigerator at low temperature (5-10 ℃) and can generally be used for about six months. If there is turbidity, mold, or precipitation in the existing mixer, it cannot be used again. When using, several 50mL polyethylene small bottles should be prepared, and the component solution from the large bottle should be poured into the small bottles. The bottles should be left at ambient temperature for 1-2 hours, and the temperature should be balanced before use. After use, it is not allowed to pour it into a large bottle to avoid contamination. The buffer solution in the bottle can be used for 2-3 days under environmental conditions>10 degree. Feem ntau, pH=7.00, pH=6.86, thiab pH=14.00 tuaj yeem siv tau ntev dua. pH=9.18 thiab pH=10.01 cov kev daws teeb meem nqus cov pa roj carbon dioxide hauv huab cua, thiab lawv cov nqi pH kuj yooj yim hloov.
Lub hom phiaj ntawm 4. pH buffer tov yog dab tsi?
(1) Calibrate pH meter ua ntej ntsuas pH.
(2) Nws yog siv los txheeb xyuas qhov tseeb ntawm pH meter, piv txwv li, pH=6 86 thiab pH =14 00. Tom qab ntsuas pH ntsuas pH, ntxig pH electrode rau hauv pH =9.18 tov, thiab xyuas seb tus nqi ntawm cov ntsuas ntsuas puas zoo ib yam nrog tus nqi pH ntawm tus qauv tov.
(3) Txheeb xyuas seb lub ntsuas pH puas yuav tsum tau rov ntsuas dua thaum ntsuas qhov ntsuas dav dav. Tom qab calibrating thiab siv lub ntsuas pH, tej zaum yuav muaj drift los yog hloov. Yog li ntawd, ua ntej kev sim, ntxig cov electrode rau hauv cov txheej txheem buffer tov uas nyob ze rau cov kev ntsuas ntsuas, thiab txiav txim siab seb puas tsim nyog recalibration raws li qhov loj ntawm qhov yuam kev.
(4) Txheeb xyuas qhov ua tau zoo ntawm pH electrode.
