Answer:
Explanation:
From the given information:
A → B k₁
B → A k₂
B + C → D k₃
The rate law = [tex]\dfrac{d[D]}{dt}=k_3[B][C] --- (1)[/tex]
[tex]\dfrac{d[B]}{dt}=k[A] -k_2[B] -k_3[B][C][/tex]
Using steady-state approximation;
[tex]\dfrac{d[B]}{dt}=0[/tex]
[tex]k_1[A]-k_2[B]-k_3[B][C] = 0[/tex]
[tex][B] = \dfrac{k_1[A]}{k_2+k_3[C]}[/tex]
From equation (1), we have:
[tex]\mathbf{\dfrac{d[D]}{dt}= \dfrac{k_3k_1[A][C]}{k_2+k_3[C]}}[/tex]
when the pressure is high;
k₂ << k₃[C]
[tex]\dfrac{d[D]}{dt} = \dfrac{k_3k_1[A][C]}{k_3[C]}= k_1A \ \ \text{first order}[/tex]
k₂ >> k₃[C]
[tex]\dfrac{d[D]}{dt} = \dfrac{k_3k_1[A][C]}{k_2}= \dfrac{k_1k_3}{k_2}[A][C] \ \ \text{second order}[/tex]
