The reaction uses B) 9.0 g Br₂.
iron + bromine ⟶ product
2.0 g + x g ⟶ 11.0 g
According to the Law of Conservation of Mass, the total mass of the reactants must equal the total mass of the products.
∴2.0 + x = 11.0
x = 11.0 – 2.0 = 9.0
The reaction uses 9.0 g Br₂.
