Final answer:
The specific reaction is not provided in the question, so it is not possible to determine the value of the initial concentration [NO₂]o.
Step-by-step explanation:
The question asks for the value of the initial concentration [NO₂]o at t = 0 for the given reaction. However, the specific reaction is not provided in the question. Therefore, it is not possible to determine the value of [NO₂]o without knowing the reaction. Please provide the balanced chemical equation for the reaction.