Over the years, the thermjte reaction has been used for welding railroads, in incendiary bombs, and to ignite solid fuel rocket monitors. The reaction is Fe2O3(s) + Al(s) --- 2Fe(l) + AI2O3(s). What mass of iron (iii) oxide(rust) must be used to produce 15.0g of molten iron.

Question

Over the years, the thermjte reaction has been used for welding railroads, in incendiary bombs, and to ignite solid fuel rocket monitors. The reaction is Fe2O3(s) + Al(s) ---> 2Fe(l) + AI2O3(s). What mass of iron (iii) oxide(rust) must be used to produce 15.0g of molten iron.

DrBob222 · Answer

Fe2O3(s) + 2Al(s) ---> 2Fe(l) + AL2O3(s).
Here are the steps to work any regular stoichiometry problem.

1. Write and balance the equation. You have that.
2. Convert 15.0 g Fe to mols. mol = grams/atomic mass Fe.
3. Using the coefficients in the balanced equation, convert mols Fe to mols Fe2O3. 2 mol Fe requires 1 mol Fe2O3.
4. Now convert mols Fe2O3 to grams. g = mols x molar mass.