Question

Iron(III) oxide reacts with carbon to give iron and carbon monoxide:Fe2O3(s)+3C(s)→2Fe(s)+3CO(g)How many grams of CO are produced when 33.0 g of C reacts?

Answer 1

We will firstly convert the mass into moles to dfeine the relationship using mole ratio.

$Fe_2O_{3(s)}+3C_{(s)}\rightarrow2Fe_{(s)}+3CO_{(g)}$$\begin{gathered} _nC_{(s)}=\frac{mass}{molar\text{ }mass} \\ \\ _nC_{(s)}=\frac{33.0\text{ }g}{12\text{ }gmol^{-1}} \\ _nC_{(s)}=2.75\text{ }mol \end{gathered}$

The mole ratio between C and CO is 3:3 or 1:1. Therefore 2.75 mol of carbon would produce 2.75 mol of carbon monoxide. Using this relationship we will convert moles to mass.

$\begin{gathered} mass\text{ }CO=moles\times molar\text{ }mass \\ mass\text{ }CO=2.75\text{ }moles\times28\text{ }gmol^{-1} \\ mass\text{ }CO=77g \end{gathered}$

Answer: 77.0g of CO are produced when 33.0g of C reacts.