Exercise  - Equation Stoichiometry with Mixtures:

The FeS2 found in pyrite ore is a source of sulfur for the production of sulfuric acid. In a series of three reactions, the sulfur in FeS2 is converted to sulfur dioxide, which in turn is converted to sulfur trioxide, which forms sulfuric acid when added to water:

4FeS2  +  11O2    2Fe2O3  +  8SO2

2SO2  +  O2        2SO3  

SO3  +  H2O    H2SO4 

a.  If, as the first step in this process, 2.75 Mg of pyrite ore that is 92.6% FeS2 is reacted with excess oxygen in air, what is the maximum mass of iron(III) oxide, Fe2O3, that can be formed?

b.  If the pyrite ore is 92.6% FeS2, what is the minimum mass of ore necessary to produce 1.00 Mg of iron(III) oxide, Fe2O3?

Click here to see an example.

Return to the Stoichiometry and Mixtures Page.


Home ] Up ] Example ] [ Exercise ]