The question is: Calculate the solubility, in g/100mL, of Ca5(PO4)3OH. when it asks for solubility, is that the same as asking for the Ksp of Ca5(PO4)3OH?? so basically, i have to find the concentration of Ca2+, PO4^3- and OH- and then find the Ksp ? BUT, i thought Ksp have no units...... how can it be in g/100mL then???? any one help please?