Question

3H2 + 1 Fe2O3 —> 2Fe + 3 H2OH2OQuestion: how many grams of H2 are required to completely convert 80g of Fe2O3?

Answer 1

1.5g of H2 are required.

Step-by-step explanation:

1st) From the balanced reaction we know that 3 moles of H2 react with 1 mole of Fe2O3.

Using the molar mass of H2 (2g/mol) and Fe2O3 (160g/mol), we can calculate the grams of H2 that are needed to react with 80g of Fe203.

- 1 mole of Fe2O3 weighs 160g.

- 3 moles of H2 weight 3g.

2nd) With the grams and a mathematical rule of three we can calculate the amount of H2 needed:

`\begin{gathered} 160g\text{ Fe}_2\text{O}_3-3g\text{ H}_2 \\ 80g\text{ Fe}_2\text{O}_3-x=\frac{80g\text{ Fe}_2\text{O}_3*3g\text{ H}_2}{160g\text{ Fe}_2\text{O}_3} \\ x=1.5g\text{ H}_2 \end{gathered}`

So, 1.5g of H2 are required.