Waste
Solubility Requirements
There are many approaches that may be used to determine a chemical compound's solubility in water. If the chemical form of all materials contained in the liquid waste is known, it is possible to use one of the following methods:
Solubility Class Determination
The solubility can be determined directly from most any chemistry or physics handbook. If:
- The classification of the chemical compound is "vs" (very soluble) or "s" (soluble), the chemical compound is "readily soluble".
- The classification of the chemical compound is "i" (insoluble), "sls" (slightly soluble), or "vsls" (very slightly soluble), the chemical compound is "not readily soluble".
- The decomposed (classified as "d" (decomposed)) species of these compounds are either "vs" or "s" the parent compound is "readily soluble". If these decomposed species are simple ions then they (class d) should be considered "readily soluble".
Formal Solubility Determination:
If the formal solubility of a compound is greater than 0.003 mole/liter, then the compound is "readily soluble". Anything else is classified as "not readily soluble".
Formal solubility, Sf is given by:
Where: Ksp is the solubility product (the equilibrium constant that describes the reaction by which a precipitate dissolves in pure water to form its constituent ions),
[M] is the molar concentration of the metal ion (cation),
[A] is the molar concentration of the anion,
m is the number of moles of dissolved cation per mole of dissolved substance, and a is the number of moles of the dissolved anion per mole of dissolved substance.
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