| SOLUBILITY EQUILIBRIA |
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Solubility and precipitation are important processes |
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Natural processes |
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Formation of caverns, stalactites and stalagmites |
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Formation of kidney stones |
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Formation of dental caries |
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Those controlled by man |
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Selective precipitation of the desired products |
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Use of barium sulfate as a contrast agent |
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Solubility equilibria will allow the
quantitative calculation of the solubility of substances |
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Quantitative calculations can replace
qualitative rules |
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Quantitative
calculations can predict the conditions under which precipitation
will or will not occur |
| SOLUBILITY PRODUCT CONSTANT |
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Symbol -
Ksp |
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Verbal definition and description |
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Verbal definition |
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Verbal description |
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Mathematical definition |
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Writing solubility product constant expressions |
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Procedure |
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Examples |
| SOLUBILITY |
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Definition |
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There are two ways to express a substance’s
solubility |
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Molar solubility |
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Solubility |
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Experimental approach to determining the
solubility of a substance |
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Determining the Ksp from the
solubility of a substance |
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Procedure |
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Examples |
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Determining the solubility of a substance from
its Ksp |
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Procedure |
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Example |
| SOLUBILITY AND THE COMMON ION EFFECT |
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Review of
the common ion effect |
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Descriptions |
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Deals with the solubility of a salt in a
solution of another salt with an
ion in common |
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Explained
by Le Chatelier’s principle |
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Solubility depends only on the concentration,
not on the source |
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Calculations involving the common ion effect |
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Procedure |
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Examples |
| PRECIPITATION CALCULATIONS |
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Description of the ion product for precipitation
calculations |
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Definition
of the ion product |
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There are
three possible cases |
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Qc
< Ksp |
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Qc = Ksp |
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Qc > Ksp |
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Using ion products to predict precipitation |
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Procedure |
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Examples |
| pH AND SOLUBILITY |
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Recognizing when the solubility of a substance
will be affected by the pH |
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Rules of thumb |
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Explanation and illustration of the rules of
thumb |
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Qualitative examples |
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Procedure |
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Examples |
| COMPLEX-ION EQUILIBRIA |
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Complex
ions -- Definitions |
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Complex
ion |
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Coordination
compound |
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Ligands |
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Coordination number |
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Formation
of complexes |
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Examples |
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The formation of
complexes proceeds in a step-wise reaction. |
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The sum of these
step-wise reactions is an equilibrium. |
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The formation
constant and the dissociation constant |
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Equilibrium
calculations |
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Procedure |
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Example
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Calculating
the solubility of a slightly soluble salt in a solution of the complex ion |
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Procedure |
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Example |