Chapter 9, Problem 9.4P

The pyrolysis of acetaldehyde is believed to take place according to the following sequence:

$\begin{array}{c}{\text{CH}}_3\text{CHO}\stackrel{k_1}{\to }{\text{CH}}_3\cdot +\text{CHO}\cdot \\ {\text{CH}}_3\cdot +{\text{CH}}_3\text{CHO}\stackrel{k_2}{\to }{\text{CH}}_3\cdot +\text{CO}+{\text{CH}}_4\\ \text{CHO}\cdot +{\text{CH}}_3\text{CHO}\stackrel{k_3}{\to }{\text{CH}}_3\cdot +2\text{CO}+{\text{H}}_2\\ 2{\text{CH}}_3\cdot \stackrel{k_4}{\to }{\text{C}}_2{\text{H}}_6\end{array}$

1. (a) Derive the rate expression for the rate of disappearance of acetaldehyde, −r_Ac.
2. (b) Under what conditions does it reduce to the equation at the beginning of Section 9.1 on page 334?
3. (c) Sketch a reaction pathway diagram for this reaction. Hint: See margin note on page 338.