Answer :
I’m assuming in this scenario that 2.5 mols of Fe2O3 is reacting with excess reactant. Based on the balanced equation, you can see that there’s a 1:2 ratio between Fe2O3 and Fe. This means that to find the mols of Fe formed, you need to multiply the mols of Fe2O3 by 2.
2.50mol Fe2O3 * 2mol Fe/1 mol of Fe2O3 = 5.00mols Fe.