# Question #a53c0

##### 1 Answer

The usual procedure is to balance all atoms other than H and O; then balance O; then balance H.

Suppose you must balance the equation

CH₄ + O₂ → CO₂ + 2H₂O

Start with most complicated-looking molecule in the equation. This looks like CH₄.

**1. Balance all atoms other than H and O.**

Put a 1 in front of the CH₄, We start with

**1** CH₄ + O₂ → CO₂ + 2H₂O

Since we have fixed one C atom on the left, we need one C atom on the right. We put a 1 in front of the CO₂..

**1** CH₄ + O₂ → **1** CO₂ + H₂O

**2. Balance O.**

We can’t, because both O₂ and H₂O need coefficients. So we balance H instead.

**3. Balance H**.

Now we have fixed 4 H atoms on the left, so we need 4 H atoms on the right. We place a 2 in front of the H₂O.

**1** CH₄ + O₂ → **1** CO₂ + **2** H₂O

**4. Balance O.**

We have four O atoms on the right, so we need four O atoms on the left. We put a 2 in front of the O₂.

**1** CH₄ + **2** O₂ → **1** CO₂ + **2** H₂O

**5. Check That the Equation is Balanced**.

Since every formula has a coefficient, we should now have a balanced equation. Let’s check:

On the left: 1 C; 4 H; 4 O

On the right: 1 C; 4 O; 4 H.

Our balanced equation is

CH₄ + 2O₂ → CO₂ + 2H₂O