Multiple choice Which of the following is the chemical formula of superphosphate? Ca(H2PO4)2, CaSO4.2H2O Ca3(PO4)3 Ca(NO3)2, NH4NO3 Ca(H2PO4)2 None of these Reveal answer Fill a bubble to check yourself A Correct answer Explanation This option is correct because when calcium phosphate is heated with concentrated H2SO4, it forms a mixture of primary phosphates of calcium and gypsum. Hence, it is called the superphosphate of lime.