How Many Moles React?

Question

Consider the reaction of 75.0 g of oxygen as follows:

4Fe + 3O2 ---> 2Fe2O3

How many moles of oxygen react?

How many moles of iron must react?

How many moles of product form?

What mass of product forms?

Answer 1

75.0g O2 x 1mol O2/32 g O2 = 2.34 mols O2

2.34 mols O2 x 4mol Fe/ 3mol O2 = 3.12 mols Fe

3.12 mols Fe x 2mol Fe2O3/ 4mol Fe = 1.56 mols Fe2O3

1.56mols Fe2O3 x 160g Fe2O3/ 1mol Fe2O3 = 250g Fe2O3