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Acetic acid correlation coefficient

Other examples of linear correlations of log rate coefficients with — H0 have been reported though most of them are deficient in some respect. Satchell474 observed such a correlation in the dedeuteration of anisole and benzene in various aqueous or acetic acid solutions of sulphuric acid, and aqueous perchloric acid, media at 25 °C. First-order rate coefficients are given in Table 127 along with those for dedeuteration of [4,5-2H2]-l,3,5-trimethoxybenzene and -2-hy-droxy-l,3-dimethoxybenzene475. For the ortho- andpara-monodeuterated anisoles the slopes of the log rate versus — H0 plots were the same for aqueous sulphuric acid and for acetic acid-sulphuric acid so that it was concluded that the A-l mechanism therefore applied to non-aqueous media as well as to aqueous media. The fact that the slope of the log rate coefficient versus —H0 plot was less (1.12) for benzene in aqueous perchloric acid than that (1.36) previously found in aqueous... [Pg.203]

Thomas and Long488 also measured the rate coefficients for detritiation of [l-3H]-cycl[3,2,2]azine in acetic acid and in water and since the rates relative to detritiation of azulene were similar in each case, a Bronsted correlation must similarly hold. The activation energy for the reaction with hydronium ion (dilute aqueous hydrochloric acid, = 0.1) was determined as 16.5 with AS = —11.3 (from second-order rate coefficients (102At2) of 0.66, 1.81, 4.80, and 11.8 at 5.02, 14.98, 24.97, and 34.76 °C, respectively). This is very close to the values of 16.0 and —10.1 obtained for detritiation of azulene under the same condition499 (below) and suggests the same reaction mechanism, general acid catalysis, for each. [Pg.215]

Hansch C, Maloney PP, Fujita T. Correlation of biological activity of phenoxy-acetic acids with Hammett subsistent constants and partition coefficients. Nature 1962 194 178-80. [Pg.489]

Increasing the excess of ethanol increases the conversion of acetic acid to ethyl acetate. To carry out the calculation more accurately would require activity coefficients to be calculated for the mixture (see Poling, Prausnitz and O Connell6 and Chapter 4). The activity coefficients depend on correlating coefficients between each binary pair in the mixture, the concentrations and temperature. [Pg.110]

It follows from all the above considerations that the acidic character of the surface is necessary for the esterification reaction. This view is supported by the parallel found by some workers [405,406] between the rate of esterification and that of other typical acid-catalysed reactions. A linear correlation was established between the rate of acetic acid—ethanol esterification and that of deisopropylation of isopropylbenzene on a series of silica—alumina, alumina—boria and alumina catalysts [406] a similar relation was found between the rate coefficient of the same esterification reaction and the cracking activity of a series of silica—alumina catalysts prepared in a different way [405]. [Pg.356]

The sensor did not respond to volatile compounds such as acetic acid, ethyl alcohol, and amines (diethylamine, propylamine, and butylamine) or to nonvolatile nutrients such as glucose, amino acids, and metal ions (potassium and sodium ions). Therefore, the selectivity of this microbial sensor was satisfactory in the presence of these different substances. The current output of the sensor was almost constant for more than 21 days and 400 assays. The microbial sensor can be used to assay sodium nitrite for a long period. In the same experiments the concentration of sodium nitrite was determined by both the sensor proposed and the conventional method (dime-thyl-a-naphtylamine method). A good correlation was obtained between the sodium nitrite concentrations determined by the two methods (correlation coefficient 0.99). [Pg.344]

The values of k2 for ring-substituted phenylacetylenes are well correlated by the Hammett relationship, using a+ constants, and p is very large, — 5-2. The p value compares well with those obtained in the acid-catalysed hydration of arylacetylene derivatives (see Table 1) and is entirely consistent with the formation of a vinyl cation 45 in which the positive charge is at the carbon next to the phenyl ring and is largely shared by it. Interestingly, the p value (by use of a+) based on k2 rate coefficients for the bromination of styrene in acetic acid is — 4-5. [Pg.209]

The TLSER methodology has been successfully applied to develop correlation equations for a wide variety of solvent-dependent properties and processes [350, 364-369]. Some examples are the characterization of other solvent polarity, acidity, and basicity scales [364], the acidities of substituted acetic acids in various solvents [365], the basicities of substituted dimethylamines in various solvents [366], the decarboxylation kinetics of 3-carboxybenzisoxazole [367], the C=0 stretching frequencies of substituted pyrrolidin-2-ones [368], and gas-water distribution coefficients [369]. [Pg.467]

Correlation coefficients shoving the relation of Zn to Fe, Mn, organic carbon and particle size in sediments extracted vith either acetic acid, hydroxylamine hydrochloride in 0.01 nitric acid, ammonium oxalate, ammonium acetate, or concentrated nitric acid. English data vcre log transforried for statistical analysis. [Pg.590]

Experimental studies were carried out to derive correlations for mass-transfer coefficients, reaction kinetics, liquid holdup and pressure drop for the new catalytic packing MULTIPAK (see [9,10]). Suitable correlations for ROMBOPAK 6M were taken from [70] and [92], The vapor-liquid equilibrium is calculated using the modification of the Wilson method [9]. For the vapor phase, the dimerization of acetic acid is taken into account using the chemical theory to correct vapor-phase fugacity coefficients [93]. Binary diffusion coefficients for the vapor phase and for the liquid phase are estimated via the method purposed by Fuller et al. and Tyn and Calus, respectively (see [94]). Physical properties like densities, viscosities and thermal conductivities are calculated from the methods given in [94]. [Pg.339]

For the application system involving acetic acid in Chapter 9, the above representation in Eq. (2.3) is not accurate enough. The reason is that acetic acid can exhibit association leading to dimerization in the vapor phase. Hayden and O Connell used the virial equation of state tmncated after the second term. They developed a correlation for the second virial coefficient of polar, nonpolar, and associating species based on the critical temperamre and pressure, the dipole moment, and the mean radius of gyration. Association of like and unlike molecules is described with the adjustable association parameter. Pure component and binary values for the association parameter are available in the Aspen Physical Property System. For detail calculations in the vapor phase, please refer to the above Hayden and O Connell paper and also to Aspen Physical Property System. ... [Pg.12]

Fourteen local anesthetics were applied in this procedure on silica gel HPTLC plates and eleven mobile phases were used in the experiments. The selection was performed by searching for the lowest absolute correlation coefficient. The lowest absolute correlation coefficient was obtained by combination of mobile phase 1 and 3, composed respectively of cyclohexane-benzene-diethylamine (75 15 10) and n-butanol-glacial acetic acid-water (8 2 2). The combination of these mobile phases yielded a separation response value of 95.9%. [Pg.94]


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See also in sourсe #XX -- [ Pg.225 , Pg.228 ]




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