Chemistry
posted by Brittany .
In the following reaction, how many grams of ferrous sulfide will produce 0.56 grams of iron oxide?
4FeS+7O2>2Fe2O3+4SO2
The molar mass of ferrous sulfide is 87.92 grams and that of iron oxide is 159.7

Write and balance the equation.
Convert 0.56 g Fe2O3 to mols. mols = g/molar mass.
Convert mols Fe2O3 to mols FeS using the coefficients in the balanced equation.
Then convert mols FeS to grams. g = mols x molar mass. 
the equation says that 4 moles of FeS produce 2 moles of Fe2O3.
So, you use twice as many moles of FeS as you get in Fe2O3.
So, how many moles of Fe2O3 is .56g?
Use twice that many moles of FeS, then convert that into grams.