The initial rate is:
![\[ \text{Initial rate} = (\Delta[A])/(\Delta t) = (\Delta[B])/(\Delta t)\]](https://img.qammunity.org/2024/formulas/chemistry/high-school/owmlv71y5hg9uiqwoex2tutjypgpfmd2te.png)
To calculate the initial rate of a reaction, you need the change in concentration of a reactant or product over a short period of time (Δ[A] or Δ[B]) and the corresponding change in time (Δt) at the very beginning of the reaction. The initial rate can be represented as:
![\[ \text{Initial rate} = (\Delta[A])/(\Delta t) = (\Delta[B])/(\Delta t)\]](https://img.qammunity.org/2024/formulas/chemistry/high-school/owmlv71y5hg9uiqwoex2tutjypgpfmd2te.png)
However, without additional information about the reaction and the rate expression, it's not possible to calculate the initial rate from just the initial concentrations of the reactants ([NO]0 and [O2]0).
The initial rate depends on the reaction order with respect to each reactant and the rate constant (k) for the specific reaction. The rate expression could be first-order, second-order, etc., and the rate law for the reaction would specify how the concentrations of the reactants affect the rate.