Examples of unexpected solubility behaviour caused by particle size effects

2 Examples of unexpected solubility behaviour caused by particle size effects 

In the following examples the unexpected pH dependence observed in nnmerous experimental studies is discussed in terms of a particle size distribntion 

Fignre VIl-20 Effect of different solubility limiting particle size fractions along an experimental solnbility curve determined with ciystalhne Th02(cr) (lg/100 mL solution) [1989MOO]. The particle size fraction distribntion assumed for the calculation is given in Table VII-25. The solubility curves for the different fractions approach constant values at low pH when the corresponding fraction is completely dissolved. 

It should be emphasised that the calculations shown in the two examples above are not considered to reflect exactly the experimental conditions and particle/crystallite size distributions in these studies. However, they point out important problems in the interpretation of solubility data for oxides or oxyhydroxides of tetravalent metal ions  

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