Analysis titration data

Values for fQi and K 2 for acids of the form H2A are determined from a least-squares analysis of data from a potentiometric titration. 

Table 2 pA), values of various monobasic acids and aminium ions as determined by Hyperquad analysis of titration data at 1 x 10 3 M in anhydrous ethanol, T = 25.0 °C... 

As with gravimetric analysis, the weight of the sample (the denominator in Equation (4.33)) is determined by direct measurement in the laboratory or by weighing by difference. The weight of the analyte in the sample is determined from the titration data via a stoichiometry calculation. As discussed previously, we calculate moles of substance titrated (in this case, the analyte) as in Equation (4.21) ... 

Sahai, N. Sverjensky D.A. (1997 a) Evaluation of externally consistent parameters for the triple layer model by the systematic analysis of oxide surface titration data. Geochim. Cosmochim. Acta 61 2801-2826 Sahai, N. Carroll, S.A. Roberts, S. O Day,... 

Table III Analysis of some conductometric titration data for the latices...

If we assume as a model that cleavage of one mole of double bond leads to one mole of acid and one mole of aldehyde, we would expect to find —35 mmoles of acid in the first stage and 70 mmoles of acid at the end of aldehyde oxidation. The difference between total acid formation in the first and second stages of reaction should reflect the amount of aldehyde oxidized. The analysis of the total acid titration data indicates that only 57% (20/35 X 100% ) of the expected amount of acid is formed in the first stage. Between 33-39 mmoles of acid are formed in the second stage, which is in the range expected from oxidation of — 35 mmoles of aldehyde. 

Analysis of the total acid titration data indicates that 33-39 mmoles of acid and peracid have been formed from aldehyde oxidation. Furthermore, 34-36 mmoles of aldehyde should have been formed in the first stage and oxidized in the second stage. If aldehyde had been oxidized solely to peracid, the active oxygen determination should have showed 34-36 mmoles of peracid instead of at the most 13 mmoles (meq./2). Enough acid but not enough peracid has been formed. This means that there are at least two paths by which aldehyde can be oxidized to acid, one of which involves peracid formation. 

Provided the described experimental procedure is followed, there seems to be little restriction in the use of the analysis. Typical data obtained by conductometric titration for the sulfonate contents of a variety of pulps and lignin are shown in Table 7.7.1 along with data obtained by other methods. 

A plot of p([Cu2 ]/[Cu7ot]) 3S a function of pH for three separate titrations fall on a single curve despite up to fivefold differences in measured dissolved copper concentration at a given pH (Figure 2). This behavior of the ratio [Cu2+]/[Cujot] is indicative of the formation of mononuclear hydrolysis species and excludes the possibility that the observed reduction in free cupric ion may have been caused by precipitation of Cu(0H)2 (solid) or the formation of polynuclear complexes. Analysis of data for p[Cu2+], pECujoj] and pH in the pH range 7.7 to 10.8 indicated the presence of two hydrolysis species (CuOH and Cu(0H)2) whose stability constants are given in Table I. Our value of the stability constant for the monohydroxo complex (106.48) falls... 

Scatchard plot analysis of data for river water titrations was conducted for values of [Gujot] 2 10 H. This was done because of apparent non-ideal electrode behavior at [Cujot]... 

It has been argued that EEC is a mere artifact (120). In an attempt to establish the existence of the EEC effect, a collection of thermodynamic data collected for the binding of 136 drugs to their receptors revealed strong correlation between enthalpy and entropy (116). Some have attributed these results to inaccuracies of the van t Hoff analysis that is used for the measurement of thermodynamic parameters (121). But isothermal titration calorimetry data (ITC) does not suffer from the same inaccuracies that plague the van t Hoff analysis. We have recently created a dataset that contains more than 400 entries containing structural and isothermal titration data (122). A plot of the enthalpy and entropy results in the following linear relationship ... 

Barnard T. E. and Bisogni J. J. (1985) Errors in Gran function analysis of titration data for dilute acidified waters. Water Res. 19, 393-399. 

Table Vn. Concentrations (in meq/g) of oxygen-containing functional groups in fulvic and humic acids from stream and foam samples from Como Creek and the Suwannee River, using a combination of C NMR data, elemental analysis, and potentiometric titration data.

Regression Analysis of Conductometric Titration Data using Equation 1 ... 

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