Tricalcium phosphate, Ca3(PO4)2(s), is a component of certain biomedical materials. Its solubility‐product constant at 25 °C is Ksp=1.0×10−25. In a manufacturing process, Ca3(PO4)2 is exposed to an aqueous environment that already contains 0.100 M CaCl2.
Using the data above, address the following tasks. Show complete calculations, clearly state any assumptions, and report answers with appropriate units.
(a) Write the balanced dissolution equilibrium for Ca3(PO4)2(s) and formulate the Ksp expression.
(b) Derive an algebraic expression that relates the molar solubility s of Ca3(PO4)2 to the initial Ca2+ concentration (0.100 M) and Ksp.
(c) Calculate the molar solubility of Ca3(PO4)2 in the 0.100 M CaCl2 solution at 25 °C. Clearly justify whether any approximation you employ is valid.
(d) Convert the molar solubility obtained in part (c) to milligrams of Ca3(PO4)2 that dissolve per liter of the CaCl2 solution.