You and your friends are trying to get rid of excess ethanol via the dehydrogenation of

ethanol (C2H5OH) to acetaldehyde (C2H4O) on metal surfaces which occurs via a sequence of elementary

steps given by:

C2H5OH + 2 C2H5O + H

C2H5O+ C2H4O + H

H + H H2 + 2

C2H4O C2H4O+

in which steps 1, 3, and 4 are quasi-equilibrated and () and (C2H5O) are the most abundant surface intermediates.

1) Obtain a rate equation for the rate of C2H5OH consumption. Then, obtain the equivalent rate

equation if step 2 was reversible. Hint: The surface reaction (step 2) is slow.

2) What inequality (in terms only of rate constants and reactant or product concentrations) must be satisfied for the quasi-equilibrated assumption of step 1 to be valid?