The balanced equation for the complete combustion of heptane is C7H16 + 11 O2 = 7 CO2 + 8 H2O. The formula for heptane is C7H16.
A combustion reaction is generally defined as a reaction with atmospheric oxygen that produces carbon dioxide and water. A balanced equation ensures that the same amount of atoms are present on both sides of the equation. The numbers in front of each component of the reaction indicate the number of each molecule present. For the combustion of heptane, one molecule of heptane and 11 molecules of oxygen produce seven molecules of carbon dioxide and eight molecules of water.