The value of the Solubility Product Constant for calcium sulfite is Write the reaction that corresponds to this K sp value. K sp values are found by clicking on the \"Tables\" link. Use the pull-down menus to specify the state of each reactant or product. If a box is not needed leave it blank. Solution calcium sulfide = CaS CaS (s) + H2O <------------> Ca +2 (aq) + S -2 (aq) Ksp = 8.0 x 10 -6 .