Answer the following questions based on the following unbalanced reaction _Fe+_O2 -> _Fe2O3

Question

a. How many moles of oxygen gas will be able to react with 3 moles of iron?

b. How many grams of ferric oxide would be produced from 7 moles of O2?

Answer 1

First, you must write the balanced equation:

4Fe + 3O₂ ===> 2Fe₂O₃ ... balanced equation

a) 3 moles of O₂ react with 4 moles of Fe. This is the mole ratio we need to use to answer part (a).

3 moles Fe x 3 moles O₂/4 moles Fe = 2.25 moles O₂ will react with 3 moles of Fe

b) 2 moles of Fe₂O₃ are produced from 3 moles of O₂. We now use this mole ratio to answer part (b).

7 moles O₂ x 2 moles F_e2O₃/3 moles O₂ = 4.67 moles Fe₂O₃ produced from 7 moles of O₂

4.67 moles Fe₂O₃ x 159.7 g/mol = 746 g Fe₂O₃ produced from 7 moles of O₂