The chemical system containing the simultaneous equilibria involves the precipitation of calcium oxalate in the presence of a wea diprotic acid, oxalic acid. Ca2+(aq)+C2O42(aq)H2C2O4(aq)+H2O(l)HC2O4(aq)+H2O(l)CaC2O4(s)H3O+(aq)+HC2O4(aq)H3O+(aq)+C2O42(aq) You added 10 drops of 6.0MHCl to the solution of calcium chloride and oxalic acid. The addition of H3O+shifts the oxalic acid equilibrium to the 2 2 the oxalate ion concentration. The of oxalate ion concentration in the calcium oxalate equilibrium causes the solid calcium oxalate 2 as the equilibrium shifts to the 2