I need to know the amount of inorganic precursors to add ,to induce supersaturation so as to further synthesize using co precipitation.
Normally I use Ksp values and calculate solubility and using activity coefficients calculate amount required.
But how to calculate for hydrated salts?
Both the hydrated salts crystallization from aq. sol. and those hydrated salt crystals dissolution to aq. sol. is largely governed by the equilibrium diagram for the solution and those hydrated salt(s), where saturation curves for those salts, and possibly also for the anhydrous salt, can be located. That diagram indicates which salt(s) can crystallize from that solution. Crystallization from the salt aq. sol. is chiefly governed by thermodynamic equilibrium, even when supersaturation occurs, since the 'driving force' for crystallization refers to displacement from equilibrium. However, dissolution may possibly occur, yet not reversibly, for salts (anhydrous or hydrated) that should not crystallize from the solution at the temperature considered, if saturated, according to the equilibrium diagram. Such salt(s), which may possibly be able to dissolve, but are not able to crystallize from the solution, are often those thermodynamically less stable, hence having higher Gibbs energy, compared to those (or that) that indeed can be crystallized. There may be several hydrated salts to be considered, besides the anhydrous salt. Published data for the solubility of hydrated salt(s) is often given in terms of the stoichiometric equivalent value for the anhydrous salt, yet referring to the considered hydrated salt. Also note that there may be several crystalline allotropes for the same molecular formula. Salts with lower Gibbs energy typically tend to show lower solubility, since they are comparatively more stable as a solid. Distinct hydrated salt(s) often have the same solubility in terms of the stoichiometric equivalent value for the anhydrous salt, which may be also coincident with that for the anhydrous salt.
Is there any consolidated pdf where Ksp values of these salts are given?
I want to calculate amount of Al(NO3)3.9H2O to be added in water to induce supersaturation
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