When ionic product i.e. the product of the concentration of ions in the solution exceeds the value of solubility product, formation of precitpiate occurs. CaF2⇌Ca2++2F− Ionic product =[Ca2+][F−]2 when, [Ca2+]=1×10−2M [F−]2=(1×10−3)2M =1×10−6M ∴[Ca2+][F−]2=(1×10−2)(1×10−6)=1×10−8 In this case, Ionic product (1×10−8)> solubility product (1.7×10−10)