In the strictly scientific sense of the word, insolubility does not exist, and even those substances characterized by the most obstinate resistance to the solvent action of water may be designated as extremely difficult of solution, not as insoluble.
We have seen the importance of aqueous solu tions in Chapters 5, 14, and 16 and most recently in Chapter 17 on acids and bases.
We are going to look at two more topics, buffers and solubility equilibria, which are related to the amount of ionic compounds dissolved in water.
In biology, almost all processes must occur within a narrow pH range.
The solubility rules are related tobility equilibria.
In this chapter, we find a more complicated picture of what we thought was insoluble under the "solubility rules", as the chapter- opening quotation from Otto Witt suggests.
Predicting precipitation reactions that might occur when a mixture of solutions is mixed is important.