Question

What are the coefficients that belong in the blanks to balance the following chemical equation?

Answer 1

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