Solving this problem helps the student to understand how to find molecular formula using empirical formula and molar mass.
Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is
Fe2O3 (s) + 2 Al (s) ---> Al2O 3 (s) + 2 Fe (s)
What masses of iron(III)oxide and aluminium should be used to produce 15.0g iron? What is the maximum mass of aluminium oxide that could be produced?