To calculate the ΔH°rxn using bond energies, we’re going to use the following equation:
Balanced Reaction: H2(g) + 1/2 O2(g) → H2O(g)
*always make sure that the given reaction is balanced
Draw the structure of each compound.
If hydrogen were used as a fuel, it could be burned according to the following reaction: H2(g)+1/2 O2(g)→H2O(g).
A) Use average bond energies to calculate ΔHrxn for this reaction. (Answer for this part is -243 kJ/mol but I was unable to get this number when I tried solving it.)
B) Use average bond energies to calculate ΔHrxn for the combustion of methane (CH4).
C) Which fuel yields more energy per mole: hydrogen or methane?
D) Per gram: hydrogen or methane?
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