Answer:
9.0 moles of CaO
Step-by-step explanation:
We have the reaction equation as follows;
Fe2O3 + Ca3(PO4)2 -------> 2FePO4 + 3CaO
Now we know from the equation that;
1 mole of iron III oxide yields 3 moles of CaO
Therefore;
3 moles of iron III oxide yields 3 * 3/1
= 9.0 moles of CaO