Question

determine the rate of the following reaction:2NO (g) + O2 (g) ---------> 2NO2 (g)The concentration of NO was 0.0500 M at t= 5.0 s and 0.0225 M at t= 650.0 s. What is the average rate of reaction during this time period?_________ M/s

Answer 1

We first verify that the reaction is balanced. We have 2 nitrogens and 4 oxygens from each of the reaction, so if it is balanced.

The average rate of the reaction (vm) will be:

`v_m=-(1)/(StoichiometriCoefficient)*(\Delta\lbrack NO\rbrack)/(\Delta t)`

Where,

Delta[NO] corresponds to the concentration difference

Delta[t] is the time difference

The Stoichiometric coefficient of NO is 2

We put the minus sign because it corresponds to a reactant.

We replace known data:

`\begin{gathered} v_m=-(1)/(2)*(0.0225M-0.0500M)/(650.0s-5.0s) \\ v_m=-(1)/(2)*(0.1750M)/(645.0s)=-1.356*10^(-4)(M)/(s) \\ \end{gathered}`

So, the average rate of reaction is -1.356x10^-4M/s