Answer:
4FeS + 5O₂ ⟶ 2Fe₂O₃ + 4SO₂
Explanation:
iron(II) sulfide + oxygen ⟶ iron(III) oxide + sulfur dioxide
1. Convert the word equation to a chemical equation:
FeS + O₂ ⟶ Fe₂O₃ + SO₂
2. Put a 1 in front of the most complicated-looking formula (Fe₂O₃):
FeS + O₂ ⟶ 1Fe₂O₃ + SO₂
3. Balance Fe:
We have fixed 2 Fe on the right. We need 2 Fe on the left. Put a 2 in front of FeS.
2FeS + O₂ ⟶ 1Fe₂O₃ + SO₂
4. Balance S:
We have fixed 2 S on the left. We need 2 S on the right. Put a 2 in front of SO₂.
2FeS + O₂ ⟶ 1Fe₂O₃ + 2SO₂
5. Balance O:
We have fixed 5 O on the right. We need 5 O on the left. Oops. We need a fraction to balance O.
6. Multiply all the coefficients by 2:
4FeS + O₂ ⟶ 2Fe₂O₃ + 4SO₂
7. Balance O:
4FeS + O₂ ⟶ 2Fe₂O₃ + 4SO₂
We have fixed 10 O on the right. e need 10 O on the left. Put a 5 in front of O₂.
4FeS + 5O₂ ⟶ 2Fe₂O₃ + 4SO₂
Every formula now has a coefficient. The equation should be balanced.
8. Check that atoms balance:
Atom On the left On the right
Fe 4 4
S 4 4
O 10 10
The balanced equation is
4FeS + 5O₂ ⟶ 2Fe₂O₃ + 4SO₂