Titration mirror image curve

Figure 11.5 shows a pH curve for a titration in which the analyte is a strong acid and the titrant is a strong base. This curve is the mirror image of the curve for the titration of a strong base with a strong acid. 

The titration curve for Tricine (base) showing the position of the buffer is sketched in Figure 1-3. The curve is shown for the titration of Tricine conjugate base with H. The curve for the titration of Tricine conjugate acid with OH" would be the mirror image of that shown. The pH of the buffer is less than pK. Therefore, [Tricine ] > [Tricine°], as shown below. 

The magnitude of the break will depend on both the concentration of the acid and the concentration of the base. Titration curves at different concentrations are shown in Figure 8.2. The reverse titration gives the mirror image of these curves. The titration of 0.1 M NaOH with 0.1 M HCl is shown in Figure 8.3. The selection of the indicators as presented in the figure is discussed below. 

Titration curves for different concentrations of NH3 titrated with varying concentrations of HCl would be the mirror images of the curves in Figure 8.6. Methyl red could not be used as an indicator in dilute solutions. The titration curves for weak bases of different Ki, values (100 mL, 0.1 M) versus 0.1 M HCl are shown in Figure 8.9. In macrotitrations, one can accurately titrate a base with a of 10 using a visual indicator. 

The pH profiles in Fig. 6 may either show a change of a slope of 1 at the pif, if the incorrectly protonated form can not bind a molecule of substrate or a molecule of inhibitor at all. Thus, pH profiles for titration curves of monobasic acids have some simple properties which should be remembered. Functions (14.47) are decreasing in alkaline or in the add, with a slope of +1 or -1, respectively. Functions (14.48) are the mirror images of functions (14.47). 

Diblock copolymers were synthesised by two stepwise anionic polymerisation methods. One method produced diblock copolymer plus 30% of poly(2-vinylpyridine) homopolymer. The copolymers were dissolved in O.IM hydrochloric acid. When the pH was increased by the dropwise addition of 0.1 M sodium hydroxide, micelles with well-defined hydrodynamic diameters formed spontaneously at around pH 5. Further basification produced stable micelle structures and reacidification produced the mirror image of this titration curve. Blue swirls were observed when sodium hydroxide was added at pH4 or pH5. The micelle sizes were measured by quasielastic light scattering. It is shown that (1) it is possible to control micelUsation by pH and (2) formation of well-behaved micelles of variable hydrodynamic diameter is possible by titration of different ratios and different total polymer concentrations of poly(2-vinylpyridine/poly(2-vinylpyridine-block-PEO). Relevance to drug release systems that can remain intact and circulate for long periods within the vascular system is suggested. 17 refs. 

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