Chemistry Chegg Worksheet

1. The reaction for the Haber process, the industrial production of ammonia, is N2(g)+3H2(g)→2NH3(g) Assume that under certain laboratory conditions ammonia is produced at the rate of 6.29×10-5 mol L-1 s-1. At what rate is nitrogen consumed? At what rate is hydrogen consumed?

2. Ammonia can react with oxygen to produce nitric oxide and water: 4NH3(g)+5O2(g)→4NO(g)+6H2O(g) If the rate at which ammonia is consumed in a laboratory experiment is 4.23×10-4 mol L-1 s-1, at what rate is oxygen consumed? At what rate is NO produced? At what rate is water vapor produced?

3. A reaction has the experimental rate equation Rate=k[A]2. How will the rate change if the concentration of A is tripled? If the concentration of A is halved?

4. Second-order rate constants used in modeling atmospheric chemistry are commonly reported in units of cm3 molecule-1 s-1. Convert the following rate constants to L mol-1 s-1:

a. 3.5×10-14 cm3 molecule-1 s-1

b. 7.1×10-18 cm3 molecule-1 s-1

c. 6.1×10-30 cm3 molecule-1 s-1

5. For each of the rate laws below, what is the order of the reaction with respect to the hypothetical substances X, Y, and Z? What is the overall order?

a. Rate=k[X][Y][Z]

b. Rate=k[X]2[Y]1/2[Z]

c. Rate=k[X]1.5[Y]-1

d. Rate=k[X]/[Y]2

6. The reaction of CO(g)+NO2(g) is second-order in NO2 and zero-order in CO at temperatures less than 500 K.

a. Write the rate law for the reaction.

b. How will the reaction rate change if the NO2 concentration is halved?

c. How will the reaction rate change if the concentration of CO is doubled?

7. One reaction that destroys O3 molecules in the stratosphere is NO+O3→NO2+O2 When this reaction was studied in the laboratory, it was found to be first order with respect to both NO and O3, with a rate constant of 1.9×104 L mol-1 s-1. If [NO]=1.2×10-5 mol L-1 and [O3]=2.0×10-5 mol L-1, what is the rate of this reaction?

8. The hypothetical reaction, A+B→C, has the rate law Rate=k[A]x[B]y When [A] is doubled and [B] is held constant, the rate doubles. But the rate increases fourfold when [B] is doubled and [A] is held constant. What are the values of x and y?

9. The rate of the decomposition of hydrogen peroxide, H2O2, depends on the concentration of iodide ion present. The rate of decomposition was measured at constant temperature and pressure for various concentrations of H2O2 and of KI. The data appear below. Determine the order od reaction for each substance, write the rate law, and evaluate the rate constant.

10. Give the order with respect to each reactant and the overall order for the hypothetical reaction A+B+C→D+E which obeys the rate law Rate=k[A][B]2.