C3H8 is the chemical formula for propane, a hydrocarbon. It's not a chemical equation, but rather a molecular formula representing the composition of the molecule.

If you're looking for a chemical equation involving propane, you need to specify the reaction.

For example, the combustion of propane in the presence of oxygen would be:

C3H8 + 5O2 → 3CO2 + 4H2O

This equation shows propane (C3H8) reacting with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O).