Nitrous Oxide N2O is a strong greenhouse gas-effect gas with a global warming potential of 300 times that of carbon dioxide and is a contributor to the destruction of ozone in the stratosphere. It is relatively inert at room temperature with an activation energy for decomposition of roughly 250kj/mol. Thus, the development of catalytic methods to decompose nitrous oxide to innocuous N2 are highly desirable.
a) Use bond-dissociation enthalpy data to decide whether the decomposition of nitrous oxide to dinitrogen and oxygen is thermodynamically favorable (ΔH= (ΔH of bonds broken)-(ΔH of bonds formed); a negative ΔH indicates a favorable reaction). Note N2O has two important resonance structures, calculate ΔH for both forms.
b) The presence of additive can enhance the thermodynamic favorability of the decomposition. Write the chemical equations for the reaction of nitrous oxide with (i) H2; and (ii) CH4 . Determine the oxidation state of each atom and determine what is oxidized and what is reduced furing the decomposition. Also calculate the ΔH with (i) H2 is added; or (ii) if CH4 is added. Which additive best enhances the thermodynamic favorability? (Hint: the products do not include O2 when an additive is used?