Dicarboxylic acids, titration

When Ng is solved as a function oih = [H] (with Nj= ), we obtain the titration curve for dicarboxylic acid in terms of the dissociation constants ... 

The pronounced electron-withdrawing nature of the 1,2,5-thia-diazole ring is evidenced by the fact that its carboxylic acid derivatives are highly acidic. The titration curve of the dicarboxylic acid exhibits two breaks with and Kai, equal to 1.59 and 4.14, respectively. The monocarboxylic acid is also strongly acidic and has a piTa of 2.47, comparable to that of ornitrobenzoic acid 2.18) and pyrazine-2-carboxylic acid (pifa 2.80). In general the piTa values for the thiadiazole carboxylic acids are in fair agreement with the pica s of the corresponding p3U azine acids (see Table II). 

In a polyanhydride (a condensation polymer of a dicarboxylic acid) the end-group titration requires 36.72 mL of 0.008964 mol/L NaOH for 1.625 g of polymer. What is the average molar mass of the polymer ... 

Poly(p-phenylene) also fascinated many workers due to its cheap cost, good mechanical strength and high stability for use in electrochemical systems. In anodic oxidation and over-oxidation studies in aqueous acidic solutions of different nucleophilicity by cyclic voltammetry, two peaks were observed. The reversible first peak was attributed to poly(p-phenylene) oxidation and formation of some insertion compound, whereas the strong and irreversible second peak at higher potentials was attributed to over-oxidation of the polymer [291] and the polymer anode started degrading at acid concentrations below 13 M [292], Accordingly, the microanalytical, IR spectroscopic and acid-base titration studies showed evidence of the formation of aromatic dicarboxylic acid, phenolic compound and carbondioxide via a p-benzoquinone intermediate [291],... 

The pKj values of a homologous series (C - C ) of cyclopentyl and cyclohexyl carboxylic acids obtained at 298 K by titration have been reported and are just as expected. The proton ionization of cycloalkane-l,l-dicarboxylic acids in aqueous perchloric acid or sodium perchlorate solutions has also been studied. From the data obtained it is suggested that the solvent-solute interactions present can be related to the conformational features of the acids. 

By analogy, the anion exchangers like Amberlite IR-4 should bind preferentially the dicarboxylic acids. This is also the case. A mixture of amino acids and hydrochloric acid, which is stirred for 1 to 3 hours with sufficient resin IR-4 to give a final pH of 6 to 7, will adsorb completely the acidic amino acids and leave the neutral and basic amino acids unaffected (Cannan 1944, Cleaver et al., 1945). On the pure fraction eluted with HCl from the resin, Cannan determined the aspartic and glutamic acids separately by a combination of electrometric titrations in water and formaldehyde solutions and a gasometric ninhydrin estimation—a method well suited for work on a semi-micro scale. 

Succinic acid is a dicarboxylic acid whose curve shows a break for each titrable hydrogen. What is interesting about that Well, the acidity constants in water for succinic acid are very close to each other, so that you cannot resolve two breaks in a titration curve. You are... 

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