Analytical Chemistry

determined by the ratio [InB]/[InA]. As a general guide, the eye will register a complete change from one colour to the other wh ...

Table 5.1 A range of visual indicators for acid-base titrations Indicator pKIn Low pH colour High pH colour Experimental colour ...

(b) phenol red (phenol sulphonephthalein) Of the two colour changes undergone by this indicator only the one at pH 6.8–8.4 is co ...

To select an indicator for an acid-base titration it is necessary to know the pH of the end point before using equation (5.5) or ...

Figure 5.2 The effect of Ka on the titration^ curves for weak acids with a strong base. 50 cm^3 of 0.1 M acid is being^ titrated ...

end points and solution composition are made. These points have been considered in Chapter 3 and are used in the indicator selec ...

Table 5.3 Basic solvents. Reagents: benzoic acid (acid) and tetra-n-butyl ammonium hydroxide (base) Solvent Analyte Indicator n- ...

Table 5.4 Some representative redox reagents Oxidizing Agents observed end points are therefore pH dependent. The potential for ...

If n = 1, the range of values of E over which a colour change is observed is 0.118 volt and is shifted by 0.059 volt for each un ...

This indicator functions well giving a sharp colour change and is also resistant to oxidative decomposition. The transition pote ...

Self-indicating Reagents and Specific Indicators Potassium permanganate and iodine, which are important redox reagents, are both ...

Dissolution of metallurgical or ore samples containing iron often requires the use of hydrochloric acid. Iron(II) is readily tit ...

nity produced by extensive hydrolysis in solutions of the tetrasodium salt. The four electron-rich acetate groups together with ...

and α 4 is seen to depend on the Ka values and the pH only. The overall variations of solution composition are summarized in Fig ...

...

and its associated formation constant A representative list of formation constants defined on this basis is given in Table 5.8. ...

Secondary Complexing Agents EDTA titration solutions frequently need to be buffered to a high pH to ensure stoichiometric format ...

ammonium chloride, triethylamine and triethanolamine. Conveniently, the same reagents can provide the basis for a buffer system ...

constants for the heavy metal-EDTA complexes so that they do not react to any significant extent. Meanwhile magnesium forms only ...

Table 5.9 Some metal ion indicators for EDTA titrations ...