Assume that 7.7254 g of K3PO4 is dissolved in enough water to make 250.0 mL of solution. (a) What is the molarity of K3PO4? (b) What is the molarity of the potassium cation? (c) What is the molarity of the phosphate anion? The molar mass of K3PO4 is 212.266 g/mol.