Final answer:
To express the rate of the reaction for 2 N₂O(g) → 2 N₂(g) + O₂(g), the rate is defined in terms of the change in concentration of N₂O, N₂, and O₂, with stoichiometry coefficients used to equate the rates of reactants and products.
Step-by-step explanation:
Expressing the rate of a reaction in terms of the change in concentration of each of the reactants and products involves using the stoichiometry of the reaction. For the reaction 2 N₂O(g) → 2 N₂(g) + O₂(g), we can write the rate of reaction as follows based on the balanced equation:
- The rate of disappearance of N₂O (reactant) is -∆[N₂O]/∆t.
- The rate of formation of N₂ (product) is +∆[N₂]/∆t.
- The rate of formation of O₂ (product) is +∆[O₂]/∆t.
Because two moles of N₂O decompose to produce two moles of N₂ and one mole of O₂, the rate of disappearance of N₂O is twice the rate of O₂ formation, and the formation rates of N₂ and N₂O are equal. Thus, these rates can be equated, taking into account their stoichiometric coefficients, to give:
Rate of reaction = -∆[N₂O]/(2∆t) = ∆[N₂]/(2∆t) = ∆[O₂]/∆t