Balance this equation. If a coefficient of "1" is required, choose "blank" for that box. C2H6 + O2 → CO2 + H2O

Step 1: Write the unbalanced equation,

C₂H₆ + O₂ → CO₂ + H₂ O

There are 2 C at left hand side and 1 carbon at right hand side. So, multiply CO ₂ by 2 to balance C atoms at both side. So,

C₂H₆ + O₂ → 2 CO₂ + H₂O

Now, count number of H atoms at both sides. There are 6 H atoms at left hand side and 2 at right hand side. Multiply H₂O by 3 to balance H atoms.

C₂H₆ + O₂ → 2 CO₂ + 3 H₂O

At last, balance O atoms. There are 2 O atoms at left hand side and 3 O atoms at right hand side. Multiply O₂ with 1.5 (i. e. 3/2) to balance O atoms. i. e.

C₂H₆ + 3/2 O₂ → 2 CO₂ + 3 H₂O

Hence, the equation is balanced. If you want to make equation fraction free then multiply all equation with 2. i. e.

(C₂H₆ + 3/2 O₂ → 2 CO₂ + 3 H₂O) * 2

2 C₂H₆ + 3 O₂ → 4 CO₂ + 6 H₂O