Qhov sib txawv tseem ceeb ntawm Nernst muaj peev xwm thiab Zeta muaj peev xwm yog qhov peev xwm Nernst tau muab rau cov khoom siv roj ntsha lossis cov hluav taws xob hluav taws xob thaum lub peev xwm zeta tau muab rau kev sib cais colloidal.
Nernst muaj peev xwm thiab zeta muaj peev xwm yog cov ntsiab lus hauv lub cev chemistry uas piav qhia txog qhov sib txawv ntawm qee yam, xws li. cell membrane, electrochemical cell, membrane ntawm ib tug dispersed particle nyob rau hauv ib tug dispersion nruab nrab, thiab lwm yam.
Nernst Potential yog dab tsi?
Nernst muaj peev xwm lossis thim rov qab muaj peev xwm yog lub peev xwm hla lub cell membrane uas tawm tsam qhov sib txawv ntawm ib qho ion los ntawm daim nyias nyias. Yog li, lo lus no muaj kev siv hauv biochemistry. Peb tuaj yeem txiav txim siab lub peev xwm Nernst los ntawm qhov sib piv ntawm cov concentrations ntawm cov ion tshwj xeeb (uas yog sim hla lub cell membrane) hauv lub cell thiab sab nraum lub cell. Txawm li cas los xij, lo lus no kuj tau siv hauv electrochemistry, hais txog cov hlwb electrochemical. Qhov sib npaug uas yog siv los txiav txim qhov peev xwm Nernst yog hu ua Nernst kab zauv.
Nernst kab zauv tuaj yeem piav qhia raws li kev qhia lej uas muab kev sib raug zoo ntawm qhov muaj peev xwm txo qis thiab tus qauv txo qhov peev xwm ntawm cov khoom siv hluav taws xob. Qhov kev sib npaug no tau muaj npe tom qab tus kws tshawb fawb W alther Nernst. Tsis tas li ntawd, qhov sib npaug no tau tsim los siv lwm yam cuam tshuam rau electrochemical oxidation thiab txo cov tshuaj tiv thaiv, xws li kub thiab tshuaj lom neeg ntawm cov tshuaj lom neeg uas raug oxidation thiab txo.
Kom tau txais qhov sib npaug Nernst, peb yuav tsum xav txog cov qauv kev hloov pauv hauv Gibbs dawb lub zog uas cuam tshuam nrog electrochemical transformations uas tshwm sim hauv lub cell. Kev txo cov tshuaj tiv thaiv ntawm ib qho hluav taws xob hluav taws xob tuaj yeem muab tau raws li hauv qab no:
Ox + z e– ⟶ Red
Hauv cov thermodynamics, qhov hloov pauv lub zog dawb ntawm cov tshuaj tiv thaiv yog, E=Ereduction - Eoxidation
Peb tuaj yeem cuam tshuam Gibbs dawb zog (ΔG) rau E (muaj peev xwm sib txawv) raws li hauv qab no:
ΔG=-nFE
Qhov twg n yog tus naj npawb ntawm cov hluav taws xob hloov pauv ntawm cov tshuaj lom neeg thaum cov tshuaj tiv thaiv nce ntxiv, F yog Faraday tas li. Yog tias peb xav txog cov qauv txheej txheem, ces qhov sib npaug yog raws li hauv qab no:
ΔG0=-nFE0
Peb tuaj yeem cuam tshuam Gibbs dawb lub zog ntawm cov xwm txheej tsis zoo nrog Gibbs lub zog ntawm cov qauv txheej txheem los ntawm kev sib npaug hauv qab no.
ΔG=ΔG0 + RTlnQ
Tom qab ntawd, peb tuaj yeem hloov qhov sib npaug saum toj no rau hauv cov qauv sib npaug no kom tau txais Nernst kab zauv raws li hauv qab no:
-nFE=-nFE0 + RTlnQ
Tom qab ntawd Nernst kab zauv yog raws li nram no:
E=E0 – (RTlnQ/nF)
Zeta muaj peev xwm yog dab tsi?
Zeta muaj peev xwm yog lub peev xwm electrokinetic ntawm colloidal dispersion. Lo lus no los ntawm Greek tsab ntawv "zeta". Feem ntau, peb hu qhov no electrokinetic muaj peev xwm zeta muaj peev xwm. Hauv lwm lo lus, zeta muaj peev xwm yog qhov muaj peev xwm sib txawv ntawm qhov nruab nrab dispersion thiab cov txheej txheem nyob ruaj khov ntawm cov kua txuas mus rau cov khoom tawg ntawm colloidal dispersion. Qhov ntawd txhais tau hais tias lub sij hawm zeta muaj peev xwm muab peb qhov qhia txog tus nqi uas muaj nyob rau ntawm qhov chaw. Peb tuaj yeem lees paub ob hom zeta muaj peev xwm: zoo thiab tsis zoo zeta peev xwm. Tsis tas li ntawd, qhov peev xwm no yog qhov peb ntsuas raws li qhov nrawm ntawm cov khoom hauv d.c. hluav taws xob teb.
Daim duab 01: Ib qho Particle hauv Colloidal Suspension
Ntawm ob hom, qhov zoo zeta muaj peev xwm qhia tau tias cov khoom tawg hauv qhov kev ncua uas peb ntsuas qhov zeta muaj peev xwm muaj qhov zoo. Ntxiv mus, thaum peb tab tom txiav txim siab qhov tseem ceeb, tsis muaj qhov sib txawv tseem ceeb ntawm qhov zoo thiab qhov tsis zoo zeta muaj peev xwm.
Ntawm qhov tod tes, qhov tsis zoo zeta muaj peev xwm qhia tau tias cov khoom tawg hauv qhov kev ncua uas peb ntsuas qhov zeta muaj peev xwm muaj qhov tsis zoo; Yog li, tus nqi ntawm cov khoom tawg yog qhov tsis zoo.
Qhov txawv ntawm Nernst Peev Xwm thiab Zeta Peev Xwm yog dab tsi?
Nernst muaj peev xwm thiab zeta muaj peev xwm yog siv rau hauv lub cev chemistry. Qhov sib txawv tseem ceeb ntawm Nernst muaj peev xwm thiab Zeta muaj peev xwm yog qhov muaj peev xwm Nernst tau muab rau cov khoom siv roj ntsha lossis cov khoom siv hluav taws xob thaum lub peev xwm zeta tau muab rau kev sib cais colloidal.
Hauv qab infographic qhia ntau qhov sib txawv ntawm Nernst muaj peev xwm thiab Zeta muaj peev xwm.
Summary – Nernst Muaj Peev Xwm vs Zeta Muaj Peev Xwm
Cov ntsiab lus Nernst muaj peev xwm thiab zeta muaj peev xwm yog siv hauv chemistry lub cev. Qhov sib txawv tseem ceeb ntawm Nernst muaj peev xwm thiab Zeta muaj peev xwm yog qhov muaj peev xwm Nernst tau muab rau cov khoom siv roj ntsha lossis cov khoom siv hluav taws xob thaum lub peev xwm zeta tau muab rau kev sib cais colloidal.
