Yuav ua li cas kom pH meter's pH electrode kom raug
Thaum lub ph electrode ntawm peb PH meter muaj qhov kev ntsuas loj, peb yuav tsum paub tias qee yam tau pib cuam tshuam rau ph electrode ntawm PH meter.
Qhov "kev puas tsuaj" ntawm qhov sib xyaw ph electrode ntawm PH 'meter', qhov tshwm sim yog qhov rhiab heev gradient txo, cov lus teb qeeb, thiab kev nyeem ntawv rov ua tsis zoo. Tej zaum nws yuav tshwm sim los ntawm peb yam hauv qab no. Feem ntau, cov neeg siv khoom tuaj yeem siv cov txheej txheem tsim nyog los kho nws.
(1) Lub qhov muag hluav taws xob thiab cov kua dej sib txuas yog cov kab mob, thiab cov av tuaj yeem ua tib zoo tshem tawm nrog txhuam zoo, paj rwb pob lossis tshuaj txhuam hniav. Lub npog tiv thaiv ntawm lub taub hau ntawm qee lub plhaub yas pH electrodes tuaj yeem raug tshem tawm, uas ua rau kev ntxuav yooj yim dua. Yog tias cov pa phem hnyav, koj tuaj yeem siv cov tshuaj ntxuav tes los ntxuav nws raws li txoj kev dhau los.
(2) Cov tshuaj siv sab nraud yog qias neeg. Rau lub rechargeable electrode, koj tuaj yeem npaj cov tshuaj KCl tshiab thiab ntxiv rau nws. Nco ntsoov tias nws yuav tsum tau nchuav tawm thaum ntxiv nws thawj zaug thiab zaum ob, txhawm rau ntxuav cov kab noj hniav sab hauv ntawm cov electrode.
(3) Kev laus ntawm cov iav rhiab zaj duab xis: Soak lub qhov muag hluav taws xob nrog 0.1mol/L dilute hydrochloric acid rau 24 teev. Yaug nrog dej ntshiab, tom qab ntawd soak hauv electrode soaking tov rau 24 teev. Yog hais tias tus passivation loj heev, koj tuaj yeem tsau qhov qis kawg ntawm cov electrode hauv 4 feem pua ntawm hydrofluoric acid tov rau 3 mus rau 5 vib nas this (kev daws teeb meem: 4ml hydrofluoric acid diluted nrog dej ntshiab rau 100m1), ntxuav nws nrog dej ntshiab, thiab tom qab ntawd muab tso rau ntawm electrode. Soak nyob rau hauv cov kua dej so rau 24 teev los kho nws cov khoom.
Configuration method of peb standard buffer solutions of pH meter
1. pH4, Potassium Hydrogen Phthalate Standard Buffer:
Ua kom raug hnyav 10.12g ntawm potassium hydrogen phthalate [KHC8H4O4] qhuav ntawm 115 ± 5 degree rau 2 mus rau 3 teev, ntxiv dej kom yaj thiab dilute rau 1000ml.
2. pH7, phosphate standard buffer tov (pH7.4):
Ua kom raug hnyav 4.303 g ntawm anhydrous disodium hydrogen phosphate thiab 1.179 g ntawm poov tshuaj dihydrogen phosphate, uas tau qhuav ntawm 115 ± 5 degree rau 2 mus rau 3 teev, ntxiv dej kom yaj thiab dilute rau 1000 ml.
Ntxiv ntxiv: Phosphate standard buffer solution (pH6.8) Ua kom raug hnyav 3.533g ntawm anhydrous disodium hydrogen phosphate thiab 3.387g ntawm poov tshuaj dihydrogen phosphate, qhuav ntawm 115 ± 5 degree rau 2 mus rau 3 teev, ntxiv dej kom yaj thiab dilute mus rau 1000ml.
3. pH9, borax txheem tsis:
Precisely hnyav 3.80g ntawm borax [Na2B4O7·10H2O] (ceeb toom: zam huab cua), ntxiv dej kom yaj thiab dilute mus rau 1000ml, muab tso rau hauv ib lub raj mis polyethylene, kaw kom nruj, thiab tsis txhob sib cuag nrog carbon dioxide nyob rau hauv cov huab cua.
