Chemical Forums
Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: NanoScience on May 20, 2005, 04:34:01 PM
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Can someone explain to me how Solubility Product Ksp relates to crystallization?
I know that excess Cl ions can induce crystallization, however, w/o the excess how would they relate to one another?
Also, how can you predetermine the size of the crystallite from a solution of NaCl? In turn, how can you manipulate the crystal size from a solution of NaCl? What is the smallest NaCl crystallite can you make (not theoretically... but practically)?
I want to thank those that is going to look at this post as well as those that respond to this post.
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crystallisation occurs when some of the solvent evaporates in a saturated solution. the ionic product of the solvated crystal constituents is always equal to Ksp during the crystallisation process.
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For the Case of NaCl:
When [Na]x[Cl] > Ksp, crystalization will occur.
The Solubility Product (Ksp) is just that, the product of the concentrations of the ions that form a particular ionic compound. For more complicated cases you will have to factor in the common ion effect and will have to substitute in activities for concentrations, but I think that concentrations will work well enough for your questions.
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I thought crystalization occurred a solution became super saturated. Removing more solvent and not any solute is one to make a solution super saturated. When you try to put more solute in a solution that is super saturated it'll crystalize.
The Ksp table shows you how much solute a solvent can take. That is how it relates to the question. Don't qoute me on this part though. I may have mixed up my tables.
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I thought crystalization occurred a solution became super saturated. Removing more solvent and not any solute is one to make a solution super saturated. When you try to put more solute in a solution that is super saturated it'll crystalize.
The Ksp table shows you how much solute a solvent can take. That is how it relates to the question. Don't qoute me on this part though. I may have mixed up my tables.
crystalization occurs when the solution is over-saturated (solvent cannot possibly hold all the solute), thus fine crystals form. yes super saturation is removing solvent and not any solute, but adding excess solute to a solvent is an entirely different matter and should not be confused with crystaliisation.
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O intresting. I didn't know that and I'll keep that in mind.