Acido-basic titration

The acid functionality was obtained in the range 1.95-2.05 by acido-basic titration. 

The manifold used for acido-basic titrations of strong acid with strong base using bromothymol blue as indicator added directly to the alkaline carrier solution is shown in Fig. 4.60a, while the recorder output is shown in Fig. 4.60 7. Here, all the five titration cycles made are recorded from the same starting point (5), showing the practical consequences of performing titrations at medium D values. First, the titration cycle, including the washout period, can be made as short as 12 s with an equivalence A/ of 2.2 s hence, it is necessary to acquire the readouts by means of a... 

The isothermal method with the use of a thermostat. NaoPO, Na2C03 and NaOH were determined simultaneously by an acido-basic titration (1). The P2O5 content was also checked gravimetrically. The composition of the solid phases was determined microscopically and also by Schreinemakers method. 

Figure 4.57. FI A titration of strong acid with strong base. The manifold (a) comprises a mixing chamber G, having a volume of 0.98 mL, where a well-defined concentration gradient is formed of the injected acid sample zone within the alkaline carrier solution, which also contains an acido-basic indicator. The flowthrough cell monitors colorimetrically the change of the indicator from blue to yellow as shown on the record in (b). As the color of the indicator is converted completely during each titration cycle, all curves have the same height, while their width, Ar, is a function of their individual concentration.

The introduction of conditional stability constants permits us, from a theoretical standpoint, to treat a complexation equilibrium to which are superimposed other equilibria of any nature as if it were alone, at least in some conditions. Conditional stability constants were introduced by G. Schwarzenbach 1957 to take into account acido-basic phenomena occurring simultaneously with complexation phenomena. The first case for which conditional stability constants were inuoduced concerned the titration of some metallic ions with EDTA tetraanion. The scope of their application scope was extended to other parasitic phenomena by A. Ringbom 1959. 

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