Balancing Combustion Equations
Part of Combustion · GCSE GCSE Chemistry revision
This worked example covers Balancing Combustion Equations within Combustion for GCSE Chemistry. Revise Combustion in Organic Chemistry for GCSE Chemistry with 25 exam-style questions and 15 flashcards. Use this page as part of a wider topic revision path rather than treating it as an isolated fact. It is section 5 of 13 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Topic position
Section 5 of 13
Practice
25 questions
Recall
15 flashcards
🧮 Balancing Combustion Equations
Combustion equations follow predictable patterns. Here's how to write them:
Hydrocarbon + O₂ → CO₂ + H₂O
• All carbon becomes CO₂
• All hydrogen becomes H₂O
• Balance carbons, then hydrogens, then oxygens
C₃H₈ + ?O₂ → ?CO₂ + ?H₂O
1. Carbons: 3 C atoms → 3CO₂
2. Hydrogens: 8 H atoms → 4H₂O (need 8 H total)
3. Oxygens: (3×2) + (4×1) = 10 O atoms → 5O₂
Answer: C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O(l)
2C₄H₁₀ + 9O₂ → 8CO + 10H₂O
Check: C: 2×4=8 ✓, H: 2×10=20→10H₂O ✓, O: 9×2=18; 8+10=18 ✓
Keep building this topic
Read this section alongside the surrounding pages in Combustion. That gives you the full topic sequence instead of a single isolated revision point.
Practice Questions for Combustion
What are the only products formed during the complete combustion of a hydrocarbon?
Explain why carbon monoxide (CO) is toxic to humans. [3 marks]
Quick Recall Flashcards
25 questions on Combustion — practise free
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