Thank you for the opportunity to help you with your question!
First balance the equation
CaCl2 + 2 Na3PO4 = 6 NaCl + Ca3(PO4)2 moles CaCl2 = 89.3 g /110.984 g/mol=0.805 the ratio between CaCl2 and Ca3(PO4)2 is 3 : 1 moles Ca3(PO4)2 = 0.805/3 =0.268 mass Ca3(PO4)2 = 0.268 mol x 310.17 g/mol=83.1 g
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