Calculate the heat of reaction for combustion of C2H5OH using bond energies


Reaction C2082H2085OH + 3O2082 –> 2CO2082 + 3H2082O ,
Then draw the structural formulas for each molecule showing single and double bonds. ,
C2082H2085OH has one C-C bond, five C-H bonds, one C-O bond and one O-H bond ,
add up the bond energies for a mole of each of these single bonds from your bond energy chart. ,
Now in O2082 we have O=O double bond so add up the total bond
energy for three moles of O2082. (three times the doubly bonded oxygen
bond energy) ,
CO2082 is formed O=C=O, and you have two moles of CO2082, and four
moles of C=O bonds so multiply the C=O bond energy by 4 ,
and for H2082O, bonded H-O-H you will have 6 moles of H-O bonds, so multiply the H-O bond energy by six. ,
Now to get 0394H for this reaction, simply subtract the sum of the
reactant bond energies from the sum of the product bond energies and you
have it. ,