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Determination of dissociation constants of uniprotic acids with known spectrum of acidic or basic component. HA A - + H +. C t [H + ]. C t K a. [ HA] =. [ A - ] =. [ H + ] + K a. [ H + ] + K a. s HA. s A. c A. c HA. =. +.
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Determination of dissociation constants of uniprotic acids with known spectrum of acidic or basic component
HA A- + H+ Ct [H+] Ct Ka [HA] = [A-] = [H+] + Ka [H+] + Ka sHA sA cA cHA = + Determination of dissociation constants of uniprotic acids with known spectrum of acidic or basic component D XHA XA = + R = D - XHA = D - cHAsHAT
sHA D Determination of dissociation constants of uniprotic acids with known spectrum of acidic or basic component R = D - XHA = D - cHAsHAT cHA =f (Ka)
rafa_Ka.m Determination of Pka value for an uniprotic acid with known spectrum of HA species
? Investigate the effects of extent of spectral overlapping on the determined pKa value by RAFA
Ct [H]2 [H2A] = [H]2 + Ka1 [H] + Ka1 Ka2 Ct Ka1 [H]2 [HA] = [H]2 + Ka1 [H] + Ka1 Ka2 Ct Ka1 Ka2 [A] = [H]2 + Ka1 [H] + Ka1 Ka2 Di-protic Acids R = D - XH2A = D - cH2AsH2AT cH2A =f (Ka1, Ka2)
Determination of amount and pKa values of an acid in a mixture with known spectrum of its components
Ct [H+] Ct Ka [HA] = [A-] = [H+] + Ka [H+] + Ka D = Determination of amount and pKa values of an acid in a mixture with known spectrum of its components HA A- + H+ XHA XA + + Interferences sHA sA cA + cHA = + Interferences R = D - XHA - XA = D - cHAsHAT- cA sAT
pH-metric titration of a mixture containing an acid with known spectrum of components sHA sA D R = D - XHA -XA= D - cHAsHAT - cA sAT cHA =f (C0,Ka) cA =f (C0,Ka)
rafa_CKa.m Determination of concentration and Pka values for an uniprotic acid with known spectrum of HA and A component
? Use RAFA_CKa and determine the amount and pKa values of a known acid in an unknown mixture
Rank Annihilation Factor Analysis for Spectrophotometric Study of Complex Formation Equilibria Anal. Chim. Acta 486, 109-123, 2003
M + M + nL nL ML ML n n [ [ ML ML ] ] n n K K = = n n f f [M] [L] [M] [L] C = [L] + [ [ ML ] L n C = [M] + [ [ ML ] M n n + 1 n K [L] + ( nK C – K C ) [ L] + [L] – C = 0 f f M f L L n n [ ML ] = K C [L] / ( 1 + K [L] ) n f M f n [M] = C / ( 1 + K [L] ) M f One-step complex formation equilibria
D XL = + Rank Annihilation Factor Analysis for Spectrophotometric Study of Complex Formation Equilibria XMLn sL sMLn cMLn + cL = + Interferences R = D - XL = D - cLsLT cL= f(Kf,n)
M + M + 2L ML ML 2 [L] [M] [ML2] One step complex formation (n=2) CL=0.001 KL=106.5
rafa_MLn.m Determination of stoichiometry and formation constant values for an MLn complex with known spectrum of ligand
n=1 n=3 n=2 n=4 n=5
? Create the data for ML3 system and use RAFA for determination of Kf and its stoichiometry.
MLn.m Simulation of MLn complex formation system