Final answer:
The rate of formation of NO₂ cannot be determined without specific information about the reaction and its initial conditions.
Step-by-step explanation:
The rate of formation of NO₂ in a chemical reaction can be determined using the initial rates method. However, the given question does not provide any specific information about the reaction or its initial conditions, so it is not possible to calculate the rate of formation of NO₂.
Please provide more information about the reaction and its initial concentrations in order to determine the rate of formation of NO₂.