Reaction Mechanisms/Kinetics In-Class Practice Problems
1. Nitrogen pentoxide reacts with nitric oxide in the gas phase according to the
The following mechanism has been proposed.
(a) Assume that the steady-state approximation can be applied to NO and derive an 3
equation for the rate of production of NO. 2
(b) How does the rate of production of NO relate to the rate of consumption of NO? 225
2. A. Lindemann (Trans Faraday Soc., 17, 598(1922)) proposed the following mechanism for a unimolecular gas reaction
The species A* is an enegized molecule that is present in low concentrations.
(a) Apply the steady-state approximation to A* and obtain an expression for the rate
(i.e., d[Y]/dt or d[Z]/dt) in terms of [A], k, k, and k. 1-12
(b) Identify the conditions under which the rate is first order and those under which it
is second order, and give expressions for the observed first and second order rate
constants in terms of k, k and k. 1-12
3. The rate law for the reaction of para-hydrogen to ortho-hydrogen
Show that the following mechanism is consistent with this rate law and express k in obs
terms of the rate constants for the individual steps of the reaction mechanism.
k1para；H(g)，，？2H(g) fast equilibrium 2k-1