Alcohol is used as a source of fuel for some automobiles. The standard molar enthalpy of formation of ethanol C2H5OH(l) is -277.6 kJ/mol. For the balanced reaction equation of ethanol use: C2H5OH(l) + 3O2 --> 2CO2 + 3H2O.

Ethanol is a liquid, but all the other chemicals in this reaction are gases. What is the enthalpy change of this reaction in kJ/mol?

Explanation:

Hello!

In this case, according to the given chemical reaction, it is possible to calculate the enthalpy change of the reaction via:

Since the enthalpy of formation of oxygen is 0. Thus, given the enthalpies of formation of gaseous carbon dioxide and water, we obtain:

Best regards!

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."