Calcium hydrogen phosphate is a component of plant fertilizers (a source of phosphate). It is a relatively insoluble hydrated ionic compound, CaHPO4·2H2O, with a Ksp of 2.7×10-7 at 25°C
a) Write a balanced equation describing a saturated solution of CaHPO4·2H2O, and write the Ksp expression.
b) "Hard" water contains relatively high concentrations of dissolved calcium ions. Calculate the solubility (in molarity) of CaHPO4·2H2O at 25°C in hard water that initially contains 95 mg/L of Ca2+
c) Imagine you will add this fertilizer solution to soil (earth) that is acidic, because there are pine trees growing in the area. How will the low pH affect the solubility equilibrium of CaHPO4·2H2O? Name the "effect" involved?