_C⁸H¹⁸+_O²-__CO²+H²O? ?

The chemical equation you provided is not balanced. To balance it, we need to ensure that the number of atoms of each element is the same on both sides of the equation.

The balanced equation is:

C₈H₁₈ + O₂ → CO₂ + H₂O

This equation represents the combustion of octane (C₈H₁₈) in the presence of oxygen (O₂) to produce carbon dioxide (CO₂) and water (H₂O).

2_C⁸H¹⁸ _O² __16_CO² + 18H²O