Answer to Question #70163 in General Chemistry for Lauren

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.

Answer 1

Fe2O3(s) + 2Al(s) = 2Fe(l) + Al2O3(s)

n(Fe) = 15.0g/55.8g/mol = 0.269 mol
n(Fe2O3) = 0.269mol/2 = 0.135 mol
m(Fe2O3) = 0.135mol*159.7g/mol = 21.6 g