Gaseous ozone 03 undergoes decomposition according to the stoichiometric equationTwo alter...

Gaseous ozone 03 undergoes decomposition according to the stoichiometric equation

Two alternative mechanisms have been proposed to accounl for this reaction:

a. Derive rate laws for the formation of 02 for each of these mechanisms.

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b. Thermodynamic measurements give standard enthalpies of formation for each of the following species at 298 K:

Substance	AH°2gs (kJ mol-1)
O2C?)	0.0
O3C?)	t42.3
O(g)	249.4

The observed activation enthalpy A//* for the overall reac tion 2O3 → 3O2, is 125.5 kJ mol-1 of O3. Sketch a curve of enthalpy (per mole of 03) vs. reaction coordinate for each of the two proposed mechanisms. Label the curves with numeri cal values for the ∆H between reactants, products, intermedi ates, and transition states.

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c. Can you exclude either of these mechanisms on the basis of the thermodynamic and activation enthalpy values of part (b)? Explain your answer.

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d. Devise a kinetic procedure for distinguishing between the two mechanisms. State clearly the nature of the experiments you would perform and what results you would use to make the distinction.