Chapter 17, Problem 17E.1BE

(a)

Interpretation Introduction

Interpretation:

The reaction mechanism for the decomposition of ${\text{A}}_{\text{2}}$ is:

    ${\text{A}}_{\text{2}}\underset{{\text{k}}_{\text{a}}^{\text{'}}}{\overset{{\text{k}}_{\text{a}}}{\rightleftarrows }}\text{A+A}\text{U}\stackrel{{\text{k}}_{\text{b}}}{\to }\text{H}$

Where U is unstable helix, and H is the stable form of helix, the reaction of A and B is first order in each species and the return of U to A $\text{+}$ B is first order in U.  The reaction of U to H is first order in U.  The rate law expression has to be deduced for the rate of formation of H by assuming a pre-equilibrium.

(b)

Interpretation Introduction

Interpretation:

The reaction mechanism for the decomposition of ${\text{A}}_{\text{2}}$ is:

    ${\text{A}}_{\text{2}}\underset{{\text{k}}_{\text{a}}^{\text{'}}}{\overset{{\text{k}}_{\text{a}}}{\rightleftarrows }}\text{A+A}\text{U}\stackrel{{\text{k}}_{\text{b}}}{\to }\text{H}$

Where U is unstable helix, and H is the stable form of helix, the reaction of A and B is first order in each species and the return of U to A $\text{+}$ B is first order in U.  The reaction of U to H is first order in U.  The rate law expression has to be deduced for the rate of formation of H by assuming a steady state approximation to $\text{U}$