Ch4 (g) yields c(g) + 4h (g) (reaction for expansion)
compare the reaction for the "expansion" of methane with the reverse of the reaction that represents the standard enthalpy of formation. which properties are the same for both reactions and which are different?
1. the number of atoms of each element, 2. the state of the methane molecules, 3. the enthalpy change of the reaction, 4. the state of the carbon atoms.