Reaction Mechanisms (College Board AP® Chemistry)

The rate expression is rate = [CH₃CHO] [OH^-].

Step 1 is the rate-determining step.

OH^- is a catalyst.

Steps 2 and 3 have a lower activation energy than step 1.

It appears in the overall balanced equation but not in the elementary steps.

It is produced in one elementary step and consumed in a subsequent step.

It catalyzes the reaction without being consumed.

It is always the limiting reagent in the overall reaction.

The step with the lowest activation energy.

The step with the highest rate constant.

The step with the highest activation energy.

The step that produces the most stable intermediate.

NO₂​ (g) and NO₂⁺ (g) ​

N₂​O₅​ (g) and NO₂​ (g)

N₂​O₅​ (g) and NO₂⁺ (g) ​

NO₂⁺ (g) and NO₃⁻ (g) ​

k = k₁k₂, where k₁ is the forward rate constant of step 1 and k₂ is the rate constant of step 2.

k = k₁k₂/k_-1, where k₁ and k_-1 are the forward and reverse rate constants of step 1, and k₂ is the rate constant of step 2.

k = k₂, where k₂ is the rate constant of step 2.

k = k₁ + k₂, where k₁ is the forward rate constant of step 1 and k₂ is the rate constant of step 2.

Dissolution of the catalyst in the reaction mixture.

Electrostatic repulsion between reactants and catalyst surface.

Formation of weak covalent bonds between reactants and catalyst surface.

Physical attraction between reactants and catalyst surface through van der Waals forces.

drives the reaction to completion by consuming byproducts of the reaction.

binds temporarily to reactant molecules to lower the activation energy of the reaction.

dissociates into additional reactant molecules, thereby increasing the reaction rate.

decomposes and releases energy to increase the number of successful collisions between reactant molecules.