Entry Task: Nov 3rd Monday Sign off on Rate Law ws MAYHAN

Agenda: Go through the answers to Rate Law ws HW: Expression and Rate Law ws MAYHAN

Clear off Desks: Calculator and handout only MAYHAN

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1 2 Rate = k[A]1[B]2 3 1.62 x10-5 = k[0.0100M]1[0.0100M]2 1. For 2 A + B  C, we’ve determined the following experimental data: 1 2 a. Rate order for A is _____and B is______ b. The rate law for this reaction is:   c. The overall reaction order is_______. d. Provide the rate constant for this reaction Rate = k[A]1[B]2 3 1.62 x10-5 = k[0.0100M]1[0.0100M]2 1.62 x10-5 M/s = k= 16.2 M-2s-1 1.0 x10-6 M3 MAYHAN

2 1 Rate = k[A]2[B]1 3 2.80 x10-3 M/s = k[0.026 M]2[0.015 M]1 2. For 2 A + B  C, we’ve determined the following experimental data: 2 1 a. Rate order for A is _____and B is______ b. The rate law for this reaction is:   c. The overall reaction order is_______. d. Provide the rate constant for this reaction Rate = k[A]2[B]1 3 2.80 x10-3 M/s = k[0.026 M]2[0.015 M]1 2.80 x10-3 M/s= k= 277 M-2s-1 1.01 x10-5 M3 MAYHAN

3. The following data were measured for the reaction of nitric oxide with hydrogen: 2 NO(g) + 2 H2(g)  N2(g) + 2 H2O(g) Using these data, determine (a) the rate law for the reaction, (b) the rate constant, (c) the rate of the reaction when [NO] = 0.050 M and [H2] = 0.150 M. MAYHAN

3. Using these data, determine (a) the rate law for the reaction Exp. 1 vs. Exp. 2, we doubled the concentration of H2, the rate doubled as well. This means [H2]1 MAYHAN

3. Using these data, determine (a) the rate law for the reaction Exp. 1 vs. Exp. 2, we doubled the concentration of H2, the rate doubled as well. This means [H2]1 Exp. 2 vs. Exp. 3, we doubled the concentration of NO and the rate quadrupled or 22 . This means that NO is 2nd order [NO]2 a) Rate = k[NO]2[H2]1 MAYHAN

a) Rate = k[NO]2[H2]1 Rate 4.92 x 10-3 M/s k= = = 1.2 M-2/s-1 3. Using these data, determine (a) the rate law for the reaction, (b) the rate constant, c) the rate of the reaction when [NO] = 0.050 M and [H2] = 0.150 M. a) Rate = k[NO]2[H2]1 Rate 4.92 x 10-3 M/s k= = = 1.2 M-2/s-1 [NO]2[H2]1 [0.20M]2[0.10M]1 MAYHAN

3. Using these data, determine (a) the rate law for the reaction, (b) the rate constant, (c) the rate of the reaction when [NO] = 0.050 M and [H2] = 0.150 M. a) Rate = k[NO]2[H2]1 b) k = 1.2 M2 s1 Rate = (1.2 M2 s1) (0.050 M)2(0.150M) Rate = 4.5 x 10-4 M/s MAYHAN

2 4. Using this information, a. Rate order for A is _____and B is______ b. The rate law for this reaction is:    c. The overall reaction order is_______. d. Provide the rate constant for this reaction 2 MAYHAN

2 1 Rate = k [A]2[B] 3 1.04 M-2s-1 4. Using this information, a. Rate order for A is _____and B is______ b. The rate law for this reaction is:    c. The overall reaction order is_______. d. Provide the rate constant for this reaction 2 1 Rate = k [A]2[B] 3 0.26 x 10-9 M/s = k [1.00 x10-3M]2[0.25 x10-3M] 1.04 M-2s-1 MAYHAN

1 5. Using this information, a. Rate order for X is _____and Y is______ b. The rate law for this reaction is:    c. The overall reaction order is_______. d. Provide the rate constant for this reaction 1 MAYHAN

1 Rate = k [X] 1 0.600 s-1 5. Using this information, a. Rate order for X is _____and Y is______ b. The rate law for this reaction is:    c. The overall reaction order is_______. d. Provide the rate constant for this reaction 1 Rate = k [X] 1 6.00 x 10-3 M/s = k [1.00 x10-2 M] 0.600 s-1 MAYHAN

1 6. Using this information, a. Rate order for A is _____, B is______ , and C is_____ b. The rate law for this reaction is:    c. The overall reaction order is_______. d. Provide the rate constant for this reaction 1 MAYHAN

2 1 6. Using this information, a. Rate order for A is _____, B is______ , and C is_____ b. The rate law for this reaction is:    c. The overall reaction order is_______. d. Provide the rate constant for this reaction 1 2 MAYHAN

2 1 6. Using this information, a. Rate order for A is _____, B is______ , and C is_____ b. The rate law for this reaction is:    c. The overall reaction order is_______. d. Provide the rate constant for this reaction 1 2 MAYHAN

2 1 Rate = k [A] [B]2 3 50 M-2 s-1 6. Using this information, a. Rate order for A is _____, B is______ , and C is_____ b. The rate law for this reaction is:   c. The overall reaction order is_______. d. Provide the rate constant for this reaction 1 2 Rate = k [A] [B]2 3 6.25 x 10-3 M/s = k [0.0500 M] [0.0500 M]2 50 M-2 s-1 MAYHAN

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Calculate Rate constant: Rate = k [A]2 [B]1 1. Using this data: Rate Law: Calculate Rate constant: Rate = k [A]2 [B]1 0.26 x 10-9 M/s = k [1.00 x 10-3 M]2 [0.25 x10-3M] 1.04 M-2 s-1 MAYHAN

Calculate Rate constant: Rate = k [X]1 2. Using this data: Rate Law: Calculate Rate constant: Rate = k [X]1 6.00 x 10-3 M/s = k [1.00 x 10-2 M] 0.6 s-1 MAYHAN

3. Consider the gas-phase reaction between nitric acid oxide ad bromine at 273°C: 2NO (g) + Br2 (g)  2NOBr (g) a) Determine the rate law? **Hint get ratios between concentrations and rates. b) Calculate the average value of the rate constant for the appearance of NOBr from our four data sets. Trial [NO] (M) [Br2] (M) Initial Rate M/s 1 0.10 0.20 24 2 0.25 150 3 0.50 60 4 0.35 735 0.10 = 24_ 0.25 = 150 (0.4)m = 0.16 NO is 2nd order MAYHAN

Rate = k [NO]2[Br2] 12000 M-2 s-1 NO is 2nd order Br2 is 1st order 3. Consider the gas-phase reaction between nitric acid oxide ad bromine at 273°C: 2NO (g) + Br2 (g)  2NOBr (g) a) Determine the rate law? **Hint get ratios between concentrations and rates. b) Calculate the average value of the rate constant for the appearance of NOBr from our four data sets. Trial [NO] (M) [Br2] (M) Initial Rate M/s 1 0.10 0.20 24 2 0.25 150 3 0.50 60 4 0.35 735 (0.10)m = 24_ (0.25)m = 150 (0.20)m = 24_ (0.50)m = 60 (0.4)m = 0.16 NO is 2nd order Br2 is 1st order (0.4)m = 0.4 Rate = k [NO]2[Br2] 12000 M-2 s-1 24 M/s = k [0.10 M]2 [0.20 M] MAYHAN

A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. The following data are for Questions 4 - 9 and refer to the reaction: A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. The rate law derived for the reaction from the above data is: [A] and [B] kept constant its obvious that [C] is 1st order (0.02)m = 10_ (0.03)m = 15 (0.67)m = 0.67 B is 1st order (0.10)m = 10_ (0.20)m = 80 (0.5)m = 0.125 This is 3rd order but we need to subtract 1 for the [C] making A an 2nd order Rate = k[A]2[B][C]

A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. The following data are for Questions 4 - 9 and refer to the reaction: A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. 5. The value of the specific rate constant is: Rate = k[A]2[B][C] 10 M/s = k [0.10]2[0.02][0.04] __ 10 M/s_ __ = k [0.10]2[0.02][0.04] = 1.25 x 106 M-3s-1

A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. The following data are for Questions 4 - 9 and refer to the reaction: A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. 6. The missing rate (trial 5) in units of M/s should be: Rate = k[A]2[B][C] ? M/s = 1.25 x 106 M-3s-1 [0.05]2[0.01][0.08] 2.5 M/s

The following data are for Questions 4 - 9 and refer to the reaction: A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. 7. The rate of disappearance of C in trial 2 was (in M/s): We can compare C disappearing with the rate of Y appearing through stoich! Let’s use -1/3 ∆C/∆t = 1/2 ∆Y/∆t 1 3 1 2 [C] ∆t 15 M/s = − 3 2 22.5 M = 15M/s

A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. The following data are for Questions 4 - 9 and refer to the reaction: A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. 8. Doubling [B] would change the rate of formation Y by a factor of: Rate = k[A]2[B][C] C would double as well!

The following data are for Questions 4 - 9 and refer to the reaction: A + 2B + 3C → 2Y + Z. All data were taken at 50.0°C. 9. The rate of formation of Z in trial 3 was (in M/s): We can compare Y disappearing with the rate of Z appearing through stoich! Let’s use -1/3 ∆C/∆t = 1/2 ∆Y/∆t 1 1 2 [Z] ∆t 80 M/s = − 1 2 40 M/s = 80M/s

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