68 . E
A catalyst cannot change the position of an equilibrium, the equilibrium constant K, the ∆G°,
or the cell potential E° of a reaction.69 . B
The rate law of a mechanism is the rate law of the slow step, and the rate law of an elementary
reaction is determined by the coefficients of the reactants. In this mechanism, the rate law of
the slow step is rate = k [NO 2 ]^2.