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Qube
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Homework Statement
Determine the enthalpy of this reaction (below).
[itex]2NO_{2} \rightarrow N_{2}O_{4}[/itex]
Homework Equations
Reaction is exothermic if product is more stable than reactants.
Reaction is endothermic if the reverse were true (product less stable than reactants).
The Attempt at a Solution
I'm trying to think of all the different ways I can explain why the forward reaction is exothermic.
1) Dimerization of nitrogen dioxide; a N-N bond is being formed using the radical on the nitrogen in nitrogen dioxide.
2) The radical on the nitrogen in nitrogen dioxide makes it inherently less stable than a molecule with no radicals.
3) The nitrogen dioxide has a positive formal charge on the nitrogen and a negative formal charge on its oxygen. Positive formal charges are also present on the nitrogens in nitrogen tetraoxide along with negative formal charges on two oxygens but the entire molecule is bigger, so the charge density is likely lower.
4) Hybridization? The nitrogen of the nitrogen dioxide is sp2 hybridized (do radicals count when determining hybridization)?
Anything else I can consider in explaining why the above reaction is exothermic?