Question

If 5.05 g of Ca(OH)2 and 6.70 g of H3PO4 are available, how many moles of Ca3(Po4)2 will you produce from each?

Answer 1

a) 0.023 mol Ca3(PO4)2 from 5.05 g Ca(OH)2

b) 0.034 mol Ca3(PO4)2 from 6.70 g H3PO4

Step-by-step explanation:

• 3Ca(OH)2 + 2H3PO4 → Ca3(PO4)2 + 6H2O

∴ Mw Ca(OH)2 = 74.093 g/mol

∴ Mw H3PO4 = 97.994 g/mol

a) n Ca3(PO4)2 = (5.05 g Ca(OH)2)×(mol Ca(OH)2/74.093 g)×(mol Ca3(PO4)2/3 mol Ca(OH)2) = 0.023 mol Ca3(PO4)2

b) n Ca3(PO4)2 = (6.70 g H3PO4)×(mol H3PO4/97.994 g)×(mol Ca3(PO4)2/2 mol H3PO4) = 0.034 mol Ca3(PO4)2