# Problem: Now consider the following set of reactions:2 NO2 → 2 NO + O2, ΔH = 109 kJ/molN2O4 → 2 NO + O2, ΔH = 172 kJ/molPart AThe equations given in the problem introduction can be added together to give the following reaction:overall: N2O4 → 2 NO2However, one of them must be reversed. Which one?reaction 1:  2 NO2 → 2 NO + O2reaction 2:  N2O4 → 2 NO + O2Part BWhat is the enthalpy for reaction 1 reversed?reaction 1 reversed: 2 NO + O2 → 2 NO2Express your answer numerically in kilojoules per mole.Part CWhat is the enthalpy for the following reaction?overall: N2O4 → 2 NO2Express your answer numerically in kilojoules per mole.

###### FREE Expert Solution

For Part A) We're being asked to determine which reaction must be reversed.

Given Reactions:

reaction 1:  2 NO2 → 2 NO + O2

reaction 2:  N2O4 → 2 NO + O2

Overall reaction: N2O4 → 2 NO2

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###### Problem Details

Now consider the following set of reactions:

2 NO2 → 2 NO + O2, Δ= 109 kJ/mol

N2O4 → 2 NO + O2, Δ= 172 kJ/mol

Part A

The equations given in the problem introduction can be added together to give the following reaction:

overall: N2O4 → 2 NO2

However, one of them must be reversed. Which one?

reaction 1:  2 NO2 → 2 NO + O2

reaction 2:  N2O4 → 2 NO + O2

Part B

What is the enthalpy for reaction 1 reversed?

reaction 1 reversed: 2 NO + O2 → 2 NO2

Part C

What is the enthalpy for the following reaction?

overall: N2O4 → 2 NO2