Tus txheej txheem pH tsis yog dab tsi? Nws cov khoom yog dab tsi?
Cov tshuaj pH tsis yog cov tshuaj uas ua kom tus nqi pH ruaj khov. Yog hais tias ib qho me me ntawm cov kua qaub los yog alkali ntxiv rau cov tshuaj no, los yog cov tshuaj tiv thaiv hauv cov tshuaj ua rau me me ntawm cov kua qaub los yog alkali, thiab cov tshuaj yog diluted kom zoo, pH tus nqi ntawm cov tshuaj yog qhov ruaj khov, uas tuaj yeem tiv taus. ib qho me me ntawm cov kua qaub. Ib qho tshuaj uas nws tus nqi pH tsis hloov thaum lub hauv paus loj los yog dilute yog hu ua cov tshuaj tsis haum.
pH standard buffer muaj cov yam ntxwv hauv qab no:
(1) Tus nqi pH ntawm cov qauv kev daws teeb meem yog paub thiab ncav cuag qhov tseeb;
(2) Tus nqi pH ntawm cov qauv kev daws teeb meem muaj qhov zoo rov ua dua thiab ruaj khov, muaj peev xwm tsis muaj peev xwm loj, tus nqi me me dilution thiab qhov kub me me coefficient;
(3) Txoj kev npaj ntawm kev daws yog yooj yim;
2. Yuav ua li cas npaj pH txheem tsis tov?
Rau kev ntsuas pH dav dav, ua tiav cov pH pawg reagents (250 mL tuaj yeem npaj tau) tuaj yeem siv. Thaum npaj cov tshuaj, dej deionized yuav tsum tau siv thiab boil rau 15 mus rau 30 feeb ua ntej kom tshem tawm cov pa roj carbon dioxide yaj. Txiav lub hnab yas thiab ncuav lub reagent rau hauv lub beaker, dissolve nws nrog ib tug tsim nyog tus nqi ntawm deionized dej, yaug lub hnab, ces ncuav nws mus rau hauv 250mL volumetric hwj, dilute rau lub cim, thiab co zoo.
3. Yuav ua li cas khaws thiab siv cov tshuaj pH tsis zoo?
After the buffer solution is prepared, it should be placed in a glass bottle or polyethylene bottle (alkaline pH buffer solutions, such as pH=9.18, pH=10.01, pH=12.46, etc., should be placed in polyethylene bottles) with the bottle cap tightly closed. , stored in the refrigerator at low temperature (5-10℃), it can generally be used for about six months. If the mixer is found to be turbid, moldy or precipitated, it cannot be used further. When using, several 50mL polyethylene vials should be prepared, pour the combined solution in the large bottles into the vials, and leave them at ambient temperature for 1 to 2 hours, and wait for the temperature to balance before use. Do not pour it into a large bottle after use to avoid contamination. The buffer solution in the bottle can be used for 2 to 3 days under environmental conditions >10 degree. Feem ntau, peb txoj kev daws teeb meem ntawm pH=7.00, pH=6.86, thiab pH=14.00 tuaj yeem siv los ua ntev npaum li lub sijhawm ntev, pH tus nqi ntawm pH=9.18 thiab pH=10.01 cov kev daws teeb meem yooj yim hloov pauv vim qhov nqus ntawm carbon dioxide hauv huab cua.
