Butane, C4H10, is widely used as a fuel for disposable lighters. When one mole of butane is burned in oxygen, carbon dioxide and steam are formed and 2658 kJ of heat is evolved.
a) Write the thermochemical equation for the reaction.
First I wrote the chemical equation for the reaction:
2C4H10 + 13O2 --> 8CO2 + 10H2O
Since the problem gives the heat for one mole of butane, would the correct thermochemical equation be this:
C4H10 + 13/2O2 --> 4CO2 + 5H2O delta-H= -2658.3 kJ
?
yes.
12
Yes, that is correct. The thermochemical equation for the reaction is:
C4H10 + 13/2O2 -> 4CO2 + 5H2O ΔH = -2658.3 kJ
Yes, you are correct. The correct thermochemical equation for the combustion of butane can be written as:
C4H10 + 13/2O2 --> 4CO2 + 5H2O ΔH = -2658.3 kJ
In this equation, the stoichiometric coefficients are balanced to show that two moles of butane react with 13 moles of oxygen to produce four moles of carbon dioxide and five moles of water. The ΔH represents the enthalpy change of the reaction, which in this case is -2658.3 kJ, indicating that the reaction is exothermic.