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Question

If a 3.7 M solution of Pb₃(PO₄)₂ dissociates completely in water, what is the final [PO₄^-3]?

Answer 1

Well if it dissociates completely it will dissociate into 3 Pb²⁺ and 2 PO₄^3- ions, so the concentration of PO₄^3-

ions will be 2 x 3.7 = 7.4 moles per liter