AP Chemistry - Kinetics Test
1. The half life of 14C is 5760 years. What is the value of k?
If a piece of bone discovered in a hillside cave has only 17% of the 14C normally found in a living tissue sample, how old is it?
2. The reaction A + 2B ---> C has the following rate law: rate = k [B]2.
Propose a valid mechanism.
Explain what this means on a molecular level.
3. For the reaction 2 NO(g) + H2 (g) ---> N2O (g) + H2O (g)
at 1100 K, the data in the following table were obtained. Find the rate law and the numerical value of the rate constant.
Initial P of NO (atm) Initial P H2 (atm) Initial rate of P decreases (atm/min)
0.150 0.400 0.020
0.075 0.400 0.005
0.150 0.200 0.010
4. Show graphically and explain why T effects the rate of a reaction.
5. Why does a catalyst increase the rate of a reaction?
6. The rate D[O2]/Dt of the reaction
2 H2O2 ----> O2 + 2 H2O
is 3.45 M/s under certain conditions. Under the same conditions, what will be the value of D[H2O]/Dt, and D[H2O2]/Dt?
7. A chemist found the value of k for the decomposition of nitrous oxide, 2NO --> N2 + O2, at two different temperatures. At 970 K , k = .14 L/mol s, and at 1085 K, k = 3.7 L/mol s. What is the activation energy of this reaction? (R = 8.314 J/mol K)
8. What is "state of subdivision" and why does it effect the rate of a reaction?