How to solve enthalpy of formation when energy produced is givenWatch
When ethanol burns in oxygen under standard conditions, carbon dioxide, water and 1368 kJmol-1 of energy are produced. Calculate the enthalpy of formation of ethanol, given that the enthalpies of formation of carbon dioxide and water are -393.7 and -285.9 kJmol-1 respectively.
Im confused as first I worked out the sum of the products and i got an answer of -1645.1kJmol-1. Im not able to figure out what the enthalpy of formation of the reactants would be as from the equation it needs to total to 1368 kJmol-1
Is that 6 x 1/2 for CO2
It won’t make a difference with the calculations of O2 is wrong but yeah it’s C2H5OH + 3 O2 --> 2CO2 + 3H2O
Do you remember the definition for enthalpy of formation?
I haven’t got a calculator on me so I’ll assume the calculation is right.
Follow the arrows and use Hess’ law