What is the pH range of calcium ions in water? ?
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Ask for help: Is the presence of calcium ions in water affected by pH? If there is an impact, then in what pH range is the calcium ion content the largest?
Reply to the 2nd floor, although it is an alkali metal, it can exist in an acidic environment. The question asked by the poster is too general and has no basis for discussion.
It can be obtained by drawing: If we only consider the influence of acidity and alkalinity, the key is to first find the ionization equilibrium constant of Ca(OH)2. Then draw a graph with [Ca++] and [OH-] as the coordinate axes, of course under the specified temperature and pressure, but you need to do a little calculation here, and then you can determine how much ca++ can exist at most when [OH-] is a certain value. good luck.
I think the main considerations are chemical balance and solubility.
The pH value directly affects the concentration of Ca++ in the water. In a more acidic solution, the higher the concentration of Ca++.
The relationship between calcium ions and pH value in water is relatively large, and the pH value is high but relatively small. Acidic conditions are large and are related to anions. Fluorine, carbonate, sulfate, etc. are small, and chlorine, nitrate, etc. are large.
It should be an acidic environment, or at worst, weakly alkaline. Strongly alkaline will definitely not work.
Calculated using the solubility product constant ksp (sp is a subscript), the solubility product of Ca(OH)2 is a fixed value (can be found in the manual), and ksp=c(Ca2+)* c(OH-)^2, while c(H+) * c(OH-)=10^-14, so the calcium ion concentration under various hydrogen ion concentrations can be calculated.
There should be no specific range. I think strongly alkaline Ca(OH)2 can still exist in water. As long as no precipitation occurs and the solubility product is met (also consider the same ion effect and salt effect).
Acidic solutions are prone to alkalinity and are prone to polymerization
It can be calculated by comprehensively considering the solubility product constants of CaSO4, Ca2(PO4)3, CaH2PO4, CaCO3 and Ca(OH)2. If it is an acidic environment with CI ions, only Ca(OH)2 should be considered.