Question

3C3H8 + 20H2CrO4-->9CO2 + 10 Cr2O3 + 32H2O

What mass of chromium (III) oxide will be formed by complete reaction of 1.50g of propane with 35.0ml of 6.26M chromic acid?

Answer 1

This is a limiting reagent problem. I think the easiest way to work them is to calculate two simple stoichiometry problems using each of the reactants.
Here is a complete worked example of a limiting reagent problem. Just follow the steps. For mols H2CrO4 use mols = M x L.
http://www.jiskha.com/science/chemistry/limiting_reagent_problem.html

Answer 2

This helped me with the amount in grams of Cr2O3, but what do I do with the 2nd part, the 35.0 ml of 6.26M chromic acid?