Balancing Chemical Equations Worksheet (with answer key)

 Balance the following chemical equations by writing the correct coefficients in the blanks provided.

1. __ H₂ + __ O₂ ⟶ __ H₂O

2. __ S₈ + __ O₂ ⟶ __ SO₂

3. __ Al + __ O₂ ⟶ __ Al₂O₃

4. __ Na + __ Cl₂ ⟶ __ NaCl

5. __ CH₄ + __ O₂ ⟶ __ CO₂ + __ H₂O

6. __ Fe + __ H₂O ⟶ __ Fe₃O₄ + __ H₂

7. __ P₄ + __ O₂ ⟶ __ P₂O₅

8. __ C₃H₈ + __ O₂ ⟶ __ CO₂ + __ H₂O

9. __ K + __ H₂O ⟶ __ KOH + __ H₂

10. __ H₂O₂ ⟶ __ H₂O + __ O₂

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Answer Key

1. 2 H₂ + 1 O₂ ⟶ 2 H₂O

2. 1 S₈ + 8 O₂ ⟶ 8 SO₂

3. 4 Al + 3 O₂ ⟶ 2 Al₂O₃

4. 2 Na + 1 Cl₂ ⟶ 2 NaCl

5. 1 CH₄ + 2 O₂ ⟶ 1 CO₂ + 2 H₂O

6. 3 Fe + 4 H₂O ⟶ 1 Fe₃O₄ + 4 H₂

7. 1 P₄ + 5 O₂ ⟶ 2 P₂O₅

8. 1 C₃H₈ + 5 O₂ ⟶ 3 CO₂ + 4 H₂O

9. 2 K + 2 H₂O ⟶ 2 KOH + 1 H₂

10. 2 H₂O₂ ⟶ 2 H₂O + 1 O₂