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1. Briefly, distinguish between a rate law and a rate constant.

2. How does a reaction quotient differ from an equilibrium constant? Be brief.

3. For the reaction CHCl3(g) + Cl2(g) CCl4(g) + HCl(g) the rate law was found to be Rate = k[CHCl3][Cl2]1/2. What is the order of reaction in each component?

4. Write the mass action expression for Kp for the reaction: H2(g) + Br2(g HBr(g)

5. Write the mass action expression for Kc for the reaction: CaCO3(s CaO(s) + CO2(g)

6. The following data was collected for the reaction C6H5N2Cl(aq) C6H5Cl(aq) + N2(g)
t (min)
[C6H5N2Cl] (M)
0
0.0710
6
0.0475
12
0.0315
18
0.0207
24
0.0144
30
0.0096

Make a zero order plot of the data. Is the reaction zero order? Why or why not?

7. A rate law for a reaction was found to be Rate = k[NO2]2. The following mechanism was proposed:
2NO2(g) N2O4(g) Slow
N2O4(g) + 2CO(g) 2NO(g) + 2CO2(g) Fast

a. Write the overall reaction.
b. Is this a plausible mechanism? Why or why not?

8. Consider the exothermic reaction of nitrogen with hydrogen to give ammonia at equilibrium. Which way will the reaction shift if

a. Ammonia is added to the system?
b. The pressure is increased?
c. The temperature is increased?
d. Fe is added as a catalyst?

9. For some reaction, the following rate data was measured:
 
T (oC)
k (s-1)
250
2.72×10-10
350
4.31×10-6

a. What is the activation energy in kJ/mol?
b. What is the half-life at each temperature?