Acetic acid data

Figure 10.2. The temperature dependence of In K for the ionization of acetic acid. Data from Ref. 2.

Fig. 8. Plot of log kjko vs. av+ constants for the mercuration of 2-substituted thiophenes in acetic acid. Data from Motoyama et oi.121...

Table 7. The low frequency bridge vibrations for the cyclic dimers of formic acid and acetic acid. Data from Jacobsen, Mikawa and Brasch 68 69).

In order to reveal the importance of the basic quinuclidine N and the OH group of CD in the enantioselection, the efficiency of CD as chiral modifier of Pt was compared to those of some CD derivatives (Table 3). Two typical trifluoromethyl ketones, 1 and 4, were hydrogenated in an apolar solvent and in acetic acid. Data on ethyl pyruvate 9 hydrogenation are also schown in Table 3 for comparison. 

Uptake of substrate at an equilibrium concentration of 25 mmole substrate/kg of gel in 5% aqueous acetic acid. Data from [30]. 

FIGURE 5.32. Plots of log r/ h-n vs. reactivity number N, for nitration of AHs in acetic anhydride (O) and chlorination in acetic acid ( ). Data from Ref 11. 

Abbreviations DNB = C6H3N2O4 = l-(3,5-dinitrobenzene) DNBPy = C5H2N3O4 = 2-(3,5-dinitropyridine) DNS = C12H12NO2S = dansyl derivative. All phenyl rings (4>) are para substituted, unless otherwise indicated. means the asymmetric carbon is part of a ring structure. The mobile phase compositions were normal phase, hexane-isopropyl alcohol with between 10 and 30% v/v IPA polar organic mode, acetonitrile-ethanol 50-50% v/v with 1% acetic acid. Data taken from [35]. 

Two additional illustrations are given in Figures 6 and 7 which show fugacity coefficients for two binary systems along the vapor-liquid saturation curve at a total pressure of 1 atm. These results are based on the chemical theory of vapor-phase imperfection and on experimental vapor-liquid equilibrium data for the binary systems. In the system formic acid (1) - acetic acid (2), <() (for y = 1) is lower than formic acid at 100.5°C has a stronger tendency to dimerize than does acetic acid at 118.2°C. Since strong dimerization occurs between all three possible pairs, (fij and not... 

An electronegative substituent particularly if it is attached to the a carbon increases the acidity of a carboxylic acid As the data m Table 19 2 show all the mono haloacetic acids are about 100 times more acidic than acetic acid Multiple halogen sub stitution increases the acidity even more trichloroacetic acid is 7000 times more acidic than acetic acid ... 

A considerable body of data is available on the acidity of substituted benzoic acids Ben zoic acid Itself is a somewhat stronger acid than acetic acid Its carboxyl group is attached to an sp hybridized carbon and ionizes to a greater extent than one that is attached to an sp hybridized carbon Remember carbon becomes more electron withdrawing as its s character increases... 

Data for Titration of 50.0 ml of 0.100 M Acetic Acid with 0.100 M NaOH... 

Reimschuessel and Deget polymerized caprolactam in sealed tubes containing about 0.0205 mol HjO per mole caprolactam. In addition, acetic acid (V), sebacic acid (S), hexamethylene diamine (H), and trimesic acid (T) were introduced as additives into separate runs. The following table lists (all data per mole caprolactam) the amounts of additive present and the analysis for end groups in various runs ... 

Sodium acetate reacts with carbon dioxide in aqueous solution to produce acetic anhydride and sodium bicarbonate (49). Under suitable conditions, the sodium bicarbonate precipitates and can be removed by centrifugal separation. Presumably, the cold water solution can be extracted with an organic solvent, eg, chloroform or ethyl acetate, to furnish acetic anhydride. The half-life of aqueous acetic anhydride at 19°C is said to be no more than 1 h (2) and some other data suggests a 6 min half-life at 20°C (50). The free energy of acetic anhydride hydrolysis is given as —65.7 kJ/mol (—15.7 kcal/mol) (51) in water. In wet chloroform, an extractant for anhydride, the free energy of hydrolysis is strangely much lower, —50.0 kJ/mol (—12.0 kcal/mol) (51). Half-life of anhydride in moist chloroform maybe as much as 120 min. Ethyl acetate, chloroform, isooctane, and / -octane may have promise for extraction of acetic anhydride. Benzene extracts acetic anhydride from acetic acid—water solutions (52). 

With these kinetic data and a knowledge of the reactor configuration, the development of a computer simulation model of the esterification reaction is iavaluable for optimising esterification reaction operation (25—28). However, all esterification reactions do not necessarily permit straightforward mathematical treatment. In a study of the esterification of 2,3-butanediol and acetic acid usiag sulfuric acid catalyst, it was found that the reaction occurs through two pairs of consecutive reversible reactions of approximately equal speeds. These reactions do not conform to any simple first-, second-, or third-order equation, even ia the early stages (29). 

Continuous esterification of acetic acid in an excess of -butyl alcohol with sulfuric acid catalyst using a four-plate single bubblecap column with reboiler has been studied (55). The rate constant and the theoretical extent of reaction were calculated for each plate, based on plate composition and on the total incoming material to the plate. Good agreement with the analytical data was obtained. 

Tables 13-1, 13-2, and 13-4 include data on formic acid and acetic acid, two substances that tend to dimerize in the vapor phase according to the chemical-equilibrium expression...

Ternary-phase equilibrium data can be tabulated as in Table 15-1 and then worked into an electronic spreadsheet as in Table 15-2 to be presented as a right-triangular diagram as shown in Fig. 15-7. The weight-fraction solute is on the horizontal axis and the weight-fraciion extraciion-solvent is on the veriical axis. The tie-lines connect the points that are in equilibrium. For low-solute concentrations the horizontal scale can be expanded. The water-acetic acid-methylisobutylketone ternary is a Type I system where only one of the binary pairs, water-MIBK, is immiscible. In a Type II system two of the binary pairs are immiscible, i.e. the solute is not totally miscible in one of the liquids. 

TABLE 15-2 Spreadsheet for Right Triangular Ternary Diagram of Water/Acetic Acid/MIBK Liquid-Liquid-Equilibrium Data at 25" C in Fig. 15-7... 

TABLE 15-3 Correlation of Liquid-Liquid Equilibrium Data for Water-Acetic Acid-MIBK... 

Typical data for operation with methyl isobutyl ketone, water, acetic acid four stages 101.6-mm stage height, 152-mm-diameter column extraction, water ketone. 

FIG. 15 53 Effect of pulsing on extraction in a packed column methyl isobutyl ketone-acetic acid-water (continuous). Tower diameter = 1.58 in, 27-in depth of V4-in Raschig rings. = Vc = 7.5 to 10. To convert inches to centimeters, multiply by 2.54. [Data of Chanhy, von Berg, and Wiegandt, Ind. Eng. Chem., 47, 1153 (1.9.55), with permission. ... 

All stated pK values in this book are for data in dilute aqueous solutions unless otherwise stated, although the dielectric constants, ionic strengths of the solutions and the method of measurement, e.g. potentiometric, spectrophotometric etc, are not given. Estimated values are also for dilute aqueous solutions whether or not the material is soluble enough in water. Generally the more dilute the solution the closer is the pK to the real thermodynamic value. The pK in mixed aqueous solvents can vary considerably with the relative concentrations and with the nature of the solvents. For example the pK values for V-benzylpenicillin are 2.76 and 4.84 in H2O and H20/EtOH (20 80) respectively the pK values for (-)-ephedrine are 9.58 and 8.84 in H2O and H20/Me0CH2CH20H (20 80) respectively and for cyclopentylamine the pK values are 10.65 and 4.05 in H2O and H20/EtOH (50 50) respectively. pK values in acetic acid or aqueous acetic acid are generally lower than in H2O. 

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