Balance C₂H₄ + O₂ → CO₂ + H₂O
C₂H₄(g) + 3 O₂(g) → 2 CO₂(g) + 2 H₂O(l)
Balance an equation
C₂H₄(g)+3O₂(g)→2CO₂(g)+2H₂O(l)
Balanced
Atoms on each side
| Atom | As writtenleft : right | Balancedleft : right |
|---|---|---|
| C | 2:1 | 2:2 |
| H | 4:2 | 4:4 |
| O | 2:3 | 6:6 |
Check atoms
How to balance it, step by step
- Count the atoms of each element on both sides, as written.
- Start with the biggest formula, C₂H₄: put 1 in front of it.
- C: 2 on the left. Put 2 in front of CO₂.
- H: 4 on the left. Put 2 in front of H₂O (2 × 2 = 4).
- O: 6 on the right. Put 3 in front of O₂ (3 × 2 = 6).
- Check: C 2 = 2, H 4 = 4, O 6 = 6. Balanced.
What happens
It is a combustion reaction: a substance burns in oxygen and gives out heat and light. Ethene burns in oxygen to give carbon dioxide and water, with a smoky flame in air.
Ethene burning: quick answers
What is the balanced equation for ethene burning?
C₂H₄(g) + 3 O₂(g) → 2 CO₂(g) + 2 H₂O(l). The coefficients are 1, 3, 2 and 2. Each side then has 2 C, 4 H and 6 O.
What type of reaction is ethene burning?
It is a combustion reaction: a substance burns in oxygen and gives out heat and light. Ethene burns in oxygen to give carbon dioxide and water, with a smoky flame in air.
How do you balance C₂H₄ + O₂ → CO₂ + H₂O?
Start with the biggest formula, C₂H₄: put 1 in front of it. C: 2 on the left. Put 2 in front of CO₂. H: 4 on the left. Put 2 in front of H₂O (2 × 2 = 4). O: 6 on the right. Put 3 in front of O₂ (3 × 2 = 6). Never change a subscript, because that would change the substance.