Inorganics, solubility dilute solutions

Many organic acids are insoluble in water, and so can be prepared from their soluble salts by simply adding a dilute solution of a strong inorganic acid to their aqueous solutions Hot concentrated H2S04 flna H3P04, , , , ... 

The POM macroionic solutions are different from the traditional ionic solutions containing small inorganic ions because the soluble ions do not distribute homogeneously in dilute solutions. However, the POM solutions are still free-energy favored real solutions, which distinguishes them from colloidal suspensions. 

Most organic substances can be dissolved readily in a suitable organic solvent and some are directly soluble in water or can be dissolved in aqueous solutions of acids (basic materials) or of alkalis (acidic materials). Many inorganic substances can be dissolved directly in water or in dilute acids, but materials such as minerals, refractories, and alloys must usually be treated with a variety of reagents in order to discover a suitable solvent in such cases the preliminary qualitative analysis will have revealed the best procedure to adopt. Each case must be considered on its merits no attempt at generalisation will therefore be made. It is however of value to discuss the experimental technique of the simple process of solution of a sample in water or in acids, and also the method of treatment of insoluble substances. 

A water soluble liquid formulation (WSL) is prepared from pesticides that are highly water soluble. This is, by far, the simplest type of formulation. One distinct advantage of WSL s over other formulations is that the field spray dilutions are infinitely stable as true solutions. Pesticides that are hydrophilic and ionic, such as inorganic or organic metallic salts, often fall into this category. Unfortunately, only a small portion of all pesticides are adequately soluble in water. 

D. The acid-soluble inorganic matter and the organic material can probably be dissolved (and oxidized) together by wet ashing with HNOa + H2S04 in a Teflon-lined bomb in a microwave oven. The insoluble residue should be washed well with water and the washings combined with the acid solution. After the residue has been dried, it can be fused with one of the fluxes in Table 28-6, dissolved in dilute acid, and combined with the previous solution. 

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