Recall: The enthalpy of reaction (ΔH˚rxn) can be calculated from the reactants' and products' enthalpy of formation (∆H˚f) using the equation:
In the combustion, CH3OH(l) reacts with O2(g) to form CO2(g) and H2O(l). The chemical equation is:
CH3OH(l) + O2(g) → CO2(g) + H2O(l)
This equation is not yet balanced. To balance it, add a coefficient of 2 to H2O to balance the number of H. The equation currently looks like this:
CH3OH(l) + O2(g) → CO2(g) + 2 H2O(l)
The equation currently has 3 O in the reactant side and 4 O in the product side. We add a coefficient of 3/2 to O2 to balance the number of O. The balanced equation is:
CH3OH(l) + 3/2 O2(g) → CO2(g) + 2 H2O(l)
Hydrogen and methanol have both been proposed as alternatives to hydrocarbon fuels. Use standard enthalpies of formation to calculate the amount of heat released per kilogram of methanol fuel.
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the Enthalpy of Formation concept. You can view video lessons to learn Enthalpy of Formation. Or if you need more Enthalpy of Formation practice, you can also practice Enthalpy of Formation practice problems.