Write the reaction for combustion of CH4 include the heat term.
CH4 + 2O2 + heat ==> CO2 + 2H2O
The usual sign, which I can't do on the board, is to place a capital Greek letter, delta, for heat. Usually it is placed where I have written "heat" but more often it is placed over the arrow.
Thanks Dr. Bob
The combustion reaction of methane (CH4) can be represented by the equation:
CH4 + 2O2 → CO2 + 2H2O + Heat
In this reaction, methane reacts with oxygen gas to produce carbon dioxide, water, and heat. The heat term indicates that the reaction is exothermic, meaning that it releases energy in the form of heat.