Chemical reactions clean burning” gases

This chemical change is often called the coal gas reaction. The hydrogen gas produced from steam reacting with coal is a clean-buming fuel. However, the energy released when the hydrogen gas is burned (113 kJ/mole) is equal to the amount of energy needed for the reaction to take place. 

The reaction we wrote above describes the complete combustion of propane. Under many conditions, though, hydrocarbons such as propane may not burn cleanly or completely, and other products may be formed. One such possible reaction is the formation of formaldehyde (CH2O) and water. Write a balanced chemical equation for a reaction in which propane and oxygen gas form CH2O and H2O as products. 

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