Title: Chapter 16(1)

Total score:

10.75/12 = 89.5833% Total score adjusted by 0.0 Maximum possible score: 12

1. Average Rate 2The compound AX2 decomposes according to the equation, 2 AX2(g) => 2 AX(g) + X2(g). In one experiment, [AX2] was measured at various times, and these data recorded:Time (s) [AX2] mol/L

0 0.0500

2.0 0.0448

6.0 0.0300

8.0 0.0249

10.0 0.0209

20.0 0.0088What is the average rate from 6.0 to 20.0 seconds in mol / L s? Use 3 significant figures! [don't include units in your answer; if you want to use scientific notation, use the E format. e.g., 0.0011 is 1.1E-3

Student Response Value Correct Answer

1. 1.5E-3 100%

Equals 0.00151 (100%)Equals 0.0015 (100%)Equals 1.5E-3 (100%)Equals 1.51E-3 (100%)Equals .00151 (100%)Equals .0015 (100%)

Score: 1/1

2. Relative Rates of Substances 3Consider the reaction, 2 D(g) + 3 E(g) + F(g) => 2 G(g) + H(g) When [D] is decreasing at 0.55 mol/Ls, how quickly is [G] increasing?

Student Response Value Correct AnswerAnswer: 0.55 100% 0.550

Score: 1/1

3. Rate Law General 3What is the reaction order of Br- for a reaction with the following rate law?

Rate = k[BrO3-][Br-][H+]2

Student Response ValueCorrect Answer

1.First 100%2.Second3.Fifth4.Fourth5.Third

Score: 1/1

4. Known Rate Law, Change Conc 47Consider the reaction with the rate law, Rate = k[BrO3

-][Br-][H+]2 By what factor does the rate change if the concentration of BrO3

- is decreased by a factor of 2, that of Br- is doubled and that of H+ is doubled ?

Student Response Value Correct Answer

1. 4 100%Equals 4 (100%)Equals 4/1 (100%)

Score: 1/1

5. Known Rate Law, Change Conc 9Consider the reaction with the rate law, Rate = k[BrO3

-][Br-][H+]2 By what factor does the rate change if the concentration of BrO3

- is decreased by a factor of 4? Just put in the number as a whole number or fraction.

Student Response Value Correct Answer

1. 0.25 100%Equals 1/4 (100%)Equals 0.25 (100%)Equals .25 (100%)

Score: 1/1

6. Determine Rate Law 39Given the data below for the reaction, 2 A + 2 B + 4 C => D + E + 3 F, the reaction is 1.----- order in A, 2.----- order in B, 3.----- order in C and 4.----- order overall. USE WORDS TO FILL IN THE BLANKS NOT NUMBERS (i.e., zero, first, second etc) !!!!! :Experiment Initial conc

of A, mol/LInitial conc of B, mol/L

Initial conc of C, mol/L

Initial rate, mol/L.s

1 0.1 0.2 0.4 2 x 10-3

2 0.2 0.2 0.4 4 x 10-3

3 0.3 0.4 0.4 1.2 x 10-2

4 0.4 0.6 0.2 6.0 x 10-3

Student Response Value Correct Answer

1. first 25% Equals first (25%)2. fisrt 0% Equals first (25%)3. second 25% Equals second (25%)4. fourth 25% Equals fourth (25%)

Score: 0.75/1

7. Determine Rate Law 3For the reaction, 4 A(g) + 3 B(g) => 2 C(g), the following data were obtained at constant temperature.Experiment Initial [A],

mol/LInitial [B], mol/L Initial Rate,

M/min

1 0.200 0.150 5.00

2 0.400 0.150 10.0

3 0.200 0.300 20.0

4 0.400 0.300 40.0Which of the following is the correct rate law for the reaction?

Student Response ValueCorrect Answer

1.Rate = k[A][B]2 100%2.Rate = k[A]2[B]2

3.Rate = k[A][B]4.Rate = k[A]2[B]

Score: 1/1

8. Calculate k from Rate Law 19For the reaction, 4 A(g) + 3 B(g) => 4 C(g), the following data were obtained at constant temperature.Experiment Initial [A],

mol/LInitial [B], mol/L Initial Rate,

M/min

1 0.15 0.22 2.7 x 10-2

2 0.30 0.22 5.4 x 10-2

3 0.30 0.44 2.16 x 10-1

4 0.45 0.66 7.3 x 10-1

Calculate the value of k to 3 significant figures.

Student Response Value Correct Answer

1. 3.72 100%Equals 3.72 (100%)Equals 3.72E0 (100%)

Score: 1/1

9. Units of k 0Which of the following would be a reasonable unit for the rate constant of

a zero order reaction?

Student Response ValueCorrect Answer

1.mol/L.sec 100%2.mol/sec3.1/sec4.L/mol.sec5.no units

Score: 1/1

10. IRL 2 k 1The reaction, AB => A(g) + B(g), has a rate law, rate = k[AB]2. Calculate the rate constant in L/mol.s if it takes 13 seconds to reach an [AB] of 0.081 mol/L from an initial concentration of 0.265 mol/L. (If necessary, write scientific notation using the E-format. e.g., 0.0111 is 1.11E-2... NO SPACES!!!!)

Student Response Value Correct AnswerAnswer: 6.59E-1 100% 0.659

Score: 1/1

11. IRL 1 t 8A reaction has a rate constant of 0.00714 sec-1, how long will it take (in minutes) until 0.484 mol/L of the compound is left, if there was 0.586 mol/L at the start? (give answer to 3 sig figs using E notation)?

Student Response Value Correct AnswerAnswer: 2.68E1 0% 0.446

Score: 0/1

12. IRL 1 t 5A reaction has a rate constant of 0.0604 sec-1, how long will it take (in seconds) until 0.500 mol/L of the compound is left, if there was 0.639 mol/L at the start? (give answer to 3 sig figs using E notation)?

Student Response Value Correct AnswerAnswer: 4.06 100% 4.061

Score: 1/1

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Title: Chapter 16(1)Started: February 11, 2012 8:40 PMSubmitted: February 11, 2012 9:40 PMTime spent: 01:00:11

Total score: 7/12 = 58.3333% Total score adjusted by 0.0 Maximum possible score: 12

1. Average Rate 1The compound AX2 decomposes according to the equation, 2 AX2(g) => 2 AX(g) + X2(g). In one experiment, [AX2] was measured at various times, and these data recorded:Time (s) [AX2] mol/L

0 0.0500

2.0 0.0448

6.0 0.0300

8.0 0.0249

10.0 0.0209

20.0 0.0088What is the average rate from 8.0 to 20.0 seconds in mol / L s? Use 3 sig figs. [don't include units in your answer; if you want to use scientific notation, use the E format. e.g., 0.0011 is 1.1E-3

Student Response Value Correct Answer

1. 1.3E-3 100%

Equals 0.00134 (100%)Equals 0.0013 (100%)Equals 1.3E-3 (100%)Equals 1.34E-3 (100%)Equals .00134 (100%)Equals .0013 (100%)Equals .001341 (100%)

Score: 1/1

2. Relative Rates of Substances 4Consider the reaction, 2 D(g) + 3 E(g) + F(g) => 2 G(g) + H(g) When [D] is decreasing at 0.99 mol/Ls, how quickly is [H] increasing?

Student Response Value Correct AnswerAnswer: 0.495 100% 0.495

Score: 1/1

3. Rate Law General 7What is the overall reaction order for H+ in a reaction with the following rate law?

Rate = k[Cl2][H+]2[CO]2

Student Response ValueCorrect Answer

1.Second 100%2.First3.Fifth4.Third5.Fourth

Score: 1/1

4. Known Rate Law, Change Conc 48Consider the reaction with the rate law, Rate = k[BrO3

-][Br-][H+]2 By what factor does the rate change if the concentration of BrO3

- is decreased by a factor of 2, that of Br- is doubled and that of H+ is decreased by a factor of 2?

Student Response Value Correct Answer

1. 0.25 100%Equals 0.25 (100%)Equals 1/4 (100%)Equals .25 (100%)

Score: 1/1

5. Known Rate Law Change Conc 56For the reaction, A(g) + B(g) => AB(g), the rate is 0.783 mol/L.s when the initial concentrations of both A and B are 2.00 mol/L. If the reaction is first order in A and second order in B, what is the rate when the initial concentration of A = 2.45 mol/L and that of B = 3.85 mol/L (give answers in E notation to 3 significant figures)

Student Response Value Correct AnswerAnswer: 3.55 100% 3.55

Score: 1/1

6. Determine Rate Law 17For the reaction, 4 A(g) + 3 B(g) => 4 C(g), the following data were obtained at constant temperature.Experiment Initial [A],

mol/LInitial [B], mol/L Initial Rate,

M/min

1 0.15 0.22 2.7 x 10-2

2 0.30 0.22 5.4 x 10-2

3 0.30 0.44 5.4 x 10-2

4 0.45 0.66 8.1 x 10-2

Which of the following is the correct rate law for the reaction?

Student Response ValueCorrect Answer

1.Rate = k[A][B]2.Rate = k[A]2[B]3.Rate = k[A]2[B]2

4.Rate = k[A][B]2

5.Rate = k[A] 100%

Score: 1/1

7. Determine Rate Law 29Given the data below for the reaction, 2 A + 2 B + 4 C => D + E + 3 F, the reaction is 1.----- order in A, 2.----- order in B, 3.----- order in C and 4.----- order overall. USE WORDS TO FILL IN THE BLANKS NOT NUMBERS (i.e., zero, first, second etc) !!!!! :Experiment Initial conc

of A, mol/LInitial conc of B, mol/L

Initial conc of C, mol/L

Initial rate, mol/L.s

1 0.1 0.1 0.2 2 x 10-3

2 0.2 0.3 0.2 1.2 x 10-2

3 0.3 0.1 0.2 6 x 10-3

4 0.4 0.3 0.6 2.4 x 10-2

Student Response Value Correct Answer1. not answered 0% Equals first (25%)2. not answered 0% Equals first (25%)3. not answered 0% Equals zero (25%)4. not answered 0% Equals second (25%)

Score: 0/1

8. Calculate k from Rate Law 28Given the data below for the reaction, 2 A + 2 B + 4 C => D + E + 3 FExperiment Initial conc

of A, mol/LInitial conc of B, mol/L

Initial conc of C, mol/L

Initial rate, mol/L.s

1 0.1 0.1 0.2 2 x 10-3

2 0.2 0.3 0.2 2 x 10-3

3 0.3 0.1 0.2 2 x 10-3

4 0.4 0.3 0.4 4 x 10-3

Calculate the value of k to 3 significant figures.

Student Response Value Correct Answer

1. 0.01 0%Equals 0.0100 (100%)Equals .0100 (100%)Equals 1.00E-2 (100%)

Score: 0/1

9. Units of k 0Which of the following would be a reasonable unit for the rate constant of a zero order reaction?

Student Response ValueCorrect Answer

1.mol/L.sec2.mol/sec3.1/sec 0%4.L/mol.sec5.no units

Score: 0/1

10. IRL 1 c 2A reaction has a rate constant of 0.0200 sec-1, how much of the compound (in mol/L) is left after 6.42 sec, if there was 0.346 mol/L at the start? (give answer to 3 sig figs using E notation)?

Student Response Value Correct AnswerAnswer: 3.04E-1 100% 0.304

Score: 1/1

11. IRL 1 t 1In a first order decomposition in which the rate constant is 0.0866 sec-1, how long will it take (in seconds) until 0.399 mol/L of the compound is left, if there was 0.757 mol/L at the start? (give answer to 3 sig figs using E notation)?

Student Response Value Correct AnswerAnswer: not answered 0% 7.395

Score: 0/1

12. IRL 2 c 1The reaction, AB => A(g) + B(g), has a rate law, rate = k[AB]2 and k = 0.063 L/mol.sec. What will be the concentration of [AB] after 193 seconds from an initial concentration of 0.648 mol/L. (Use scientific notation using the E-format. e.g., 0.0111 is 1.11E-2... NO SPACES!!!!)

Student Response Value Correct AnswerAnswer: not answered 0% 0.073

Score: 0/1