Chloroacetic acid, ionization constant

The acid ionization constant of chloroacetic acid is equal to 1.40 x 10 at 25 °C. Assume that activity coefficients are equal to unity and find the hydrogen-ion concentration at the following stoichiometric molarities ... 

HC102 = 3ClOz + Cl2 + 2HzO, and turning yel in color. As judged by the conductivity of its aq solns, it is a weak acid. Its ionization constant is 1.1 xlO 2 which is about the same as for oxalic acid or chloroacetic acid(Ref 5). For more detailed description of its props, See Ref 2... 

Figure 7. Ionization constants of acids in ethanol-water mixtures vs. the dielectric constant function at 25°C. A Malonic acid (O), lactic acid (A), succinic acid ( ). (B) Cyanoacetic acid ( ), salicyclic acid ( ), glutaric acid ( ). C Chloroacetic acid (O), glycolic acid (A), isovaleric acia(D).

B) Ionization Constants. Determine the pH of 0.1 solutions of acetic, chloroacetic, and trichloroacetic acids. Convert the pH to hydrogen-ion concentration as moles per liter then calculate the ionization constants for acetic and monochloroacetic acid. 

The ionization constant of chloroacetic acid (CICH2COOH) in water is 1.528 X 10 at 0°C and 1.230 X 10 at 40°C. Calculate the enthalpy of ionization of the acid in water, assuming that AH and AS are constant over this range of temperature. 

Table IIL Thb Ionization Constant of Chloroacetic Acid from Ostwald s Dilution Law, =389.5...

In view of the foregoing, we might expect to find a correlation between the dissociation constant and the adsorbability of an organic acid. The relation holds to some extent, but there are many deviations the strongly ionized chloroacetic acid is more adsorbable than the weakly ionized acetic acid. 

Although the mechanism of eqns (7) and (8) may be a reasonable one for the breakdown of [109], for some of the more reactive species, especially those derived from chloroacetic or dichloracetic acid, it may not be, as shown by the following considerations. For this mechanism to be valid the value of fc2 calculated from the relationship /cHO- = A fc2must be (i) less than the time constant for a molecular vibration (1012-1014s-1) fii) less than the value of based on the estimated Ka and the assumption that the ionization equilibrium (7) is diffusion controlled in the thermodynamically favourable direction, i.e. k1 = 10nM-1s-1. These two conditions are easily fulfilled with the hemiacetals and the less reactive hemiorthoesters derived from pinacol monoesters (see Table 15), but with the more reactive hemiorthoesters the calculated values of k2 lie close to or are greater than the cal-... 

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