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Problem: From the bond energies given below, estimate the ΔH° for the reaction:H2(g) + I2(g) → 2HI(g)Bond energies (kJ/mol):H–H = 436H–I = 297I–I = 151

FREE Expert Solution

To calculate the ΔH°rxn using bond energies, we’re going to use the following equation:


Horxn = Hbond reactants - Hbond products


Let’s first figure out what kind of bonds and how many moles are present in each reactant and products because the given bond energies are per mole.

Balanced Reaction:  H2(g) + I2(g) → 2 HI(g)

*always make sure that the given reaction is balanced

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Problem Details

From the bond energies given below, estimate the ΔH° for the reaction:


H2(g) + I2(g) → 2HI(g)


Bond energies (kJ/mol):
H–H = 436
H–I = 297
I–I = 151

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What scientific concept do you need to know in order to solve this problem?

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