Do calcium sulfates with different amounts of crystal water have different solubilities?
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Does calcium sulfate with different amounts of crystal water, as mentioned in the title, have different solubilities? Thank you
The solubility expressed in terms of the anhydrous form is the same, but the dissolution rates of different hydrates can differ by several orders of magnitude.
Thank you. So, which one has the fastest dissolution rate: anhydrous, dihydrate, or hemihydrate? Also, for example, if a calcium sulfate solution at around 130°C is mixed with water to cool it down to around 90°C, will crystals form and cause scaling on the walls?
Thank you. So, which one has the fastest dissolution rate: anhydrous, dihydrate, or hemihydrate? Also, for example, if a calcium sulfate solution at around 130°C is mixed with water to cool it down to around 90°C, will crystals form and cause scaling on the walls?
Thank you. So, which one has the fastest dissolution rate: anhydrous, dihydrate, or hemihydrate? Also, for example, if a calcium sulfate solution at around 130°C is mixed with water to cool it down to around 90°C, will crystals form and cause scaling on the walls?
Thank you. So, which one has the fastest dissolution rate: anhydrous, dihydrate, or hemihydrate? Also, for example, if a calcium sulfate solution at around 130°C is mixed with water to cool it down to around 90°C, will crystals form and cause scaling on the walls?
Are you referring to a saturated solution of calcium sulfate or a suspension? Cooling a saturated solution from 130 degrees should not result in precipitation, as the solubility of calcium sulfate decreases as temperature rises; moreover, water has been added.
Calcium sulfate with different numbers of water molecules of crystallization has varying solubilities
Solubility of calcium sulfate: The solubility of CaSO4 is not high, and it shows a peculiar pattern of increasing first and then decreasing. For example, the solubility at 1°C is 0.12 g per 1 g of water (the same applies hereafter); at 4°C it is 0.2, and it drops to 0.161 at 1°C. Calcium sulfate is a white monoclinic crystal or crystalline powder. No odor. It is hygroscopic. 1 molecule of crystalline water is lost at 128°C, and all water is lost at 163°C. Soluble in acids, sodium thiosulfate, and ammonium salts; soluble in 400 parts of water; less soluble in hot water; very slowly soluble in glycerol; practically insoluble in ethanol and most organic solvents.
Calcium sulfate with different numbers of water molecules of crystallization has the same solubility in water