AP Chemistry Unit 5 Practice Test: Kinetics

Topic 5.1 · Apply it

For 2NO₂(g) → 2NO(g) + O₂(g), NO₂ is consumed at 0.040 M/s. At what rate is O₂ produced?

Topic 5.2 · Data analysis

What is the order of the reaction with respect to A?

Topic 5.2 · Data analysis

In experiments on A + B → C, doubling [B] while keeping [A] constant leaves the initial rate unchanged. What is the order with respect to B?

Topic 5.3 · Apply it

A first-order reaction has a rate constant k = 0.0693 s⁻¹. What is its half-life?

Topic 5.3 · Data analysis

A student plots concentration data three ways. Only the graph of ln[A] against time is a straight line. What is the order of the reaction?

Topic 5.4 · Apply it

The step 2NO(g) + O₂(g) → 2NO₂(g) is an elementary reaction. What is its rate law?

Topic 5.5 · Apply it

Raising the temperature by 10 °C often doubles a reaction's rate. What is the main reason?

Topic 5.6 · Data analysis

On an energy profile, the reactants are at 50 kJ, the transition state is at 120 kJ and the products are at 20 kJ.

What are the activation energy of the forward reaction and the enthalpy change?

Topic 5.7 · Apply it

Step 1 (slow): NO₂ + NO₂ → NO₃ + NO
Step 2 (fast): NO₃ + CO → NO₂ + CO₂
Overall: NO₂ + CO → NO + CO₂

Which species is an intermediate in this mechanism?

Topic 5.8 · Apply it

Step 1 (slow): NO₂ + NO₂ → NO₃ + NO
Step 2 (fast): NO₃ + CO → NO₂ + CO₂
Overall: NO₂ + CO → NO + CO₂

Which rate law is consistent with this mechanism?

Topic 5.9 · Apply it

Step 1 (fast, reaches equilibrium): 2NO ⇌ N₂O₂
Step 2 (slow): N₂O₂ + O₂ → 2NO₂

Using the pre-equilibrium approximation, which rate law matches this mechanism?

Topic 5.10 · Data analysis

A two-step reaction's energy profile has two peaks. The first peak is 80 kJ above the reactants. The second peak is 30 kJ above the intermediate that forms after step 1.

Which step is rate-determining?

Topic 5.11 · Concept check

How does a catalyst increase the rate of a reaction?