604 Chapter 13 - Chemical Kinetics 13.7 when the concentration of X is 0.30 M and that of Y is 0.40 M. Suppose that at a particular moment during the reaction nitric oxide (NO) is reacting at the rate of 0.066 M/s. (a) At what rate is NO2 being formed? (b) At what rate is molecular oxygen reacting? 13.8 Consider the reaction Initial Rate of [Y] (M) [X] (M) Disappearance of X (M/s) N2(8) + 3H2(8) → 2NH3(g) 0.50 0.10 0.053 0.30 Suppose that at a particular moment during the reaction molecular hydrogen is reacting at the rate of 0.074 M/s. (a) At what rate is ammonia being formed? (b) At what rate is molecular nitro- gen reacting? 0.20 0.127 0.60 0.40 1.02 0.60 0.20 0.254 0.30 0.40 0.509 Determine the overall orders of the reactions to which the following rate laws apply: (a) rate = (b) rate = k[NO]° [O2]. 13.17 k[NO2J°, k[H2] [Br2], (d) rate = 13.2 The Rate Law %3D k. (c) rate = Review Questions 13.9 Explain what is meant by the rate law of a reaction. 13.10 What are the units for the rate constants of zero- 13.18 Consider the reaction A B order, first-order, and second-order reactions? Consider the zero-order reaction: A product. (a) Write the rate law for the reaction. (b) What are the units for the rate constant? (c) Plot the rate of the reaction versus [A]. 13.11 The rate of the reaction is 1.6 x 10 M/s when the concentration of A is 0.35 M. Calculate the rate con- stant if the reaction is (a) first order in A, and (b) second order in A. 13.19 Cyclobutane decomposes to ethylene according to 13.12 On which of the following properties does the rate constant of a reaction depend: (a) reactant concen- trations, (b) nature of reactants, or (c) temperature? the equation CH3(g) 2C,H,(g) Determine the order of the reaction and the rate con- Problems stant based on the following pressures, which were recorded when the reaction was carried out at 430°C 13.13 The rate law for the reaction in a constant-volume vessel. NH (aq) + NO, (aq) N2(8) + 2H;0(!) is given by rate = k [NH] [NO]. At 25°C, the rate constant is 3.0 x 10/M s. Calculate the rate of the reaction at this temperature if [NH] = 0.26 M and [NO] = 0.080 M. Time (s) PCAHs (mmHg) 0. 400 2,000 316 %3D 4,000 13.14 Use the data in Table 13.2 to calculate the rate of 248 the reaction at the time when [F2] = 0.010 M and [CIO2] = 0.020 M. Consider the reaction 6,000 196 %3D 8,000 155 13.15 10,000 122 A + B products 13.20 The following gas-phase reaction was studied at 290°C by observing the change in pressure as a function of time in a constant-volume vessel: From the following data obtained at a certain tem- perature, determine the order of the reaction and cal- culate the rate constant. CICO,CCI3(g) →2COCI,(g) Rate (M/s) Determine the order of the reaction and the rate con- [B] (M) [A] (M) stant based on the following data: 3.20 X 10 3.20 X 10 6.40 X 10 1.50 1.50 Ask 2.50 1.50 Time (s) P (mmHg) 1.50 3.00 15.76 13.16 Consider the reaction 181 18.88 513 22.79 X + Y Z 1164 27.08 From the following data, obtained at 360 K, (a) determine the order of the reaction, and (b) de- termine the initial rate of disappearance of X where P is the total pressure. P. HW