Answer:
(a) [tex]_{4}Fe+_{3}O_{2}=_{2}Fe_{2}O_{3}[/tex]
(b) 22.9 moles of Fe
(c) 1278.8 g of Fe
Explanation:
(a) To write the equation you have to take in account that as the problem says that is oxygen in air you should write it as [tex]O_{2}[/tex]
So, first the problem is telling you that iron reacts with oxygen in air, so you should write the reactants:
[tex]Fe+O_{2}[/tex]
Then the problem says that it produces iron(III) oxide [tex]Fe_{2}O_{3}[/tex], so you should write the product:
[tex]Fe+O_{2}=Fe_{2}O_{3}[/tex]
Finally you should balance the equation, so you need to have the same quantity of each atom in both sides of the equation:
[tex]_{4}Fe+_{3}O_{2}=_{2}Fe_{2}O_{3}[/tex]
(b) You should use the stoichiometry of the balanced equation to solve this part, so:
[tex]17.15molesO_{2}*\frac{4molesFe}{3molesO_{2}}=22.9molesFe[/tex]
(c) To solve this part, you need to know that the molar mass for the Fe is [tex]55.845\frac{g}{mol}[/tex], so:
[tex]22.9molesFe*\frac{55.845gFe}{1molFe}=1278.8gFe[/tex]