Qhov sib txawv tseem ceeb ntawm qhov sib npaug ntawm qhov tsis tu ncua thiab tus nqi tas li yog qhov sib npaug tas li yog qhia siv ob qho tib si ntawm cov reactants thiab cov khoom, whereas tus nqi tas li yog qhia siv cov concentration ntawm reactants lossis khoom.
Ob leeg, qhov sib npaug tsis tu ncua thiab tus nqi tas li, yog qhov tseem ceeb rau ib qho tshuaj tiv thaiv. Qhov ntawd txhais tau tias, ntawm qhov kev tawm tsam tas li, cov xwm txheej xws li qhov kub thiab txias, tus nqi ntawm qhov sib npaug tsis tu ncua, thiab tus nqi tas li tsis hloov nrog lub sijhawm. Tsis tas li ntawd, hauv kev nthuav qhia qhov sib npaug tas li, peb yuav tsum xav txog qhov stoichiometric coefficient ib yam. Tab sis, rau tus nqi tas li, peb yuav tsum txiav txim siab tus nqi siv tsuas yog txoj kev sim.
Yuav ua li cas yog qhov Equilibrium?
Qhov sib npaug tas li yog qhov sib piv ntawm qhov sib xyaw ntawm cov khoom thiab cov concentrations ntawm reactants ntawm qhov sib npaug. Peb tuaj yeem siv lo lus no tsuas yog nrog cov kev cuam tshuam uas nyob hauv qhov sib npaug. Cov tshuaj tiv thaiv quotient thiab qhov sib npaug tas li yog tib yam rau cov tshuaj tiv thaiv uas nyob hauv qhov sib npaug.
Ntxiv mus, peb yuav tsum muab qhov no tas mus li siv cov concentrations tsa rau lub zog ntawm stoichiometric coefficients. Qhov sib npaug tas li nyob ntawm qhov ntsuas kub ntawm qhov system vim qhov kub thiab txias cuam tshuam rau kev solubility ntawm cov khoom thiab qhov ntim nthuav dav. Txawm li cas los xij, qhov sib npaug ntawm qhov sib npaug tas li tsis suav nrog cov ntsiab lus hais txog cov khoom khib nyiab uas muaj nyob hauv cov reactants lossis cov khoom. Tsuas yog cov tshuaj nyob rau hauv cov kua theem thiab gaseous theem yog xam.
Piv txwv li, qhov sib npaug ntawm acetic acid thiab acetate ion yog raws li hauv qab no:
CH3COOH ⇌ CH3COO– + H +
Qhov sib npaug tas li, Kc rau qhov kev tawm tsam no yog raws li hauv qab no:
Kc=[CH3COO–][H+]/[CH 3COOH]
Daim duab 01: Kev sib npaug ntawm qhov sib txawv ntawm cov khoom sib txawv
Tus nqi tas li yog dab tsi?
Tus nqi tas li yog tus coefficient ntawm proportionality hais txog tus nqi ntawm cov tshuaj tiv thaiv tshuaj ntawm qhov kub thiab txias rau qhov concentration ntawm cov reactants los yog cov khoom ntawm cov tshuaj tiv thaiv. Yog tias peb sau qhov sib npaug ntawm qhov sib npaug ntawm reactant A rau cov tshuaj tiv thaiv hauv qab no, nws yog raws li nram no.
aA + bB ⟶ cC + dD
R=-K [A]a [B]b
Hauv qhov tshuaj tiv thaiv no, k yog tus nqi tas li. Nws yog proportionality tas li uas nyob ntawm qhov kub thiab txias. Peb tuaj yeem txiav txim siab tus nqi thiab tus nqi tas li ntawm cov tshuaj tiv thaiv los ntawm kev sim.
Dab tsi yog qhov sib txawv ntawm qhov Equilibrium tas li thiab tus nqi tas li?
Qhov sib txawv tseem ceeb ntawm qhov sib npaug ntawm qhov tsis tu ncua thiab tus nqi tas li yog qhov sib npaug tas li yog qhia siv ob qho tib si ntawm cov tshuaj reactants thiab cov khoom, whereas tus nqi tas li yog qhia siv cov concentration ntawm cov reactants los yog cov khoom. Tsis tas li ntawd, qhov sib npaug tas li yog muab rau qhov sib npaug ntawm cov tshuaj tiv thaiv, thaum tus nqi tas li tuaj yeem muab rau txhua qhov kev tawm tsam.
Ntxiv mus, hauv kev nthuav qhia qhov sib npaug tas li, peb tuaj yeem siv qhov ntau ntawm cov tshuaj reactants thiab cov khoom lag luam nrog rau cov stoichiometric coefficients thaum, hauv kev nthuav qhia tus nqi tas li, peb tsis tuaj yeem siv cov stoichiometric coefficient vim peb yuav tsum txiav txim siab tus nqi ntawm cov khoom. tas mus li kev sim. Tsis tas li ntawd, qhov sib npaug tas li piav qhia txog qhov tsis hloov pauv cov tshuaj tiv thaiv sib xyaw, thaum tus nqi tas li piav qhia txog cov tshuaj tiv thaiv sib xyaw uas hloov nrog lub sijhawm.
Summary – Equilibrium Constant vs. Rate Constant
Hauv cov ntsiab lus, ob qho tib si, qhov sib npaug tsis tu ncua thiab tus nqi tas li, tsis hloov nrog lub sijhawm yog tias cov tshuaj tiv thaiv xws li kub tsis hloov. Txawm li cas los xij, qhov sib txawv tseem ceeb ntawm qhov sib npaug ntawm qhov tsis tu ncua thiab tus nqi tas li yog qhov sib npaug tas li yog qhia siv ob qho tib si ntawm cov tshuaj reactants thiab cov khoom, whereas tus nqi tas li yog qhia siv cov concentration ntawm reactants los yog cov khoom.
