The general chemical equation for the complete combustion of a hydrocarbon is:

C_xH_y + (x + y/4)O₂ → xCO₂ + (y/2)H₂O + energy

Where:

* C_xH_y represents the hydrocarbon, with 'x' being the number of carbon atoms and 'y' being the number of hydrogen atoms.

* O₂ represents oxygen gas.

* CO₂ represents carbon dioxide.

* H₂O represents water.

Important points:

* Complete combustion means that the hydrocarbon reacts completely with oxygen to produce only carbon dioxide and water.

* The equation is balanced, meaning that the number of atoms of each element on both sides of the equation is equal.

* The energy released during the combustion is represented by the "energy" term.

Example:

For the complete combustion of methane (CH₄):

CH₄ + 2O₂ → CO₂ + 2H₂O + energy

Note:

* The stoichiometric coefficients (the numbers in front of the chemical formulas) are determined by balancing the equation.

* The actual amount of energy released depends on the specific hydrocarbon.

* In reality, combustion is often not completely efficient and can produce other products like carbon monoxide (CO) and soot.