Chem-102-Quiz A

Chapter 12

 

Name : -----------------------------------         I.D. : -------------------       Section : --------

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  1. The following data were obtained at a certain temperature for  the reaction

2H2 (g)    +    2NO (g)        2H2O (g)    +    N2 (g)

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Experiment              [H2] (M)                [NO] (M)                Initial Rate (M/s)

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            1                      0.010                   0.025                       2.4 x 10-6

 

            2                      0.0050                 0.025                       1.2 x 10-6

 

            3                      0.010                   0.0125                     0.60 x 10-6

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Give the values of m, n, and k in the rate equation,   Rate = k [H2] n [NO] m

 

n  = 1..(1 point)                    

 

 m  = ..2..(1 point)    

 

k  =  0.384 (1 / M2.s)   or (M -2 s -1)   or (mol -2 L 2 s -1)..(2 points)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

2.   The decomposition of a compound is first order.  What is the half-life of this decomposition if 75 percent of a given sample of this compound decomposes in 60 min?

 

t1/2  =   30 min(2 points)

 

                                                                                                            P.T.O.

Quiz A (Continued)

 

  1. The rate constant of a first-order reaction is 4.60 x 10 -4 s -1 at 350 ºC.  If the activation energy is 104 kJ mol -1, calculate the temperature at which the rate constant is 8.8 x 10 -4 s -1.

 

R  =  8.314 J K -1 mol-1

 

      Temperature = 644 (or 643.8) K  OR  371 (or 370.8) ºC.(2 points)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Chem-102-Quiz B

Chapter 12

 

Name : -----------------------------------         I.D. : -------------------       Section : --------

____________________________________________________________________

 

 

  1. The following data were obtained at a certain temperature for  the reaction

 

2NO (g)    +    Cl2 (g)        2NOCl (g)   

 

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Experiment              [NO] (M)  [Cl2] (M)              Initial Rate (M/s)

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            1                      0.50                     0.50                         1.14

 

            2                      1.00                     0.50                         4.56

 

            3                      1.00                     1.00                         9.12

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Give the values of m, n, and k in the rate equation,   Rate = k [NO] n [Cl2] m

 

            n  = 2..(1 point)    

           

           m  =  1.(1 point)       

 

           k  =  9.12(1 / M2.s)   or (M -2 s -1)   or (mol -2 L 2 s-1)(2 points)

 

 

 

 

 

 

 

 

 

 

2.   The decomposition of a compound is first order.  What is the half-life of this decomposition if 75 percent of a given sample of this compound decomposes in 120 min?

 

t1/2  =   60 min(2 points)                                                                                                                                                                         P.T.O.

Quiz B (Continued)

 

  1. The rate constant of a first-order reaction is 4.60 x 10 -4 s -1 at 350 ºC.  If the activation energy is 104 kJ mol -1, calculate the temperature at which the rate constant is 5.6 x 10 -4 s -1.

 

R  =  8.314 J K -1 mol-1

 

      Temperature = 629 (or 629.2) K  OR  356 (or 356.2) ºC.(2 points)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Chem-102-Quiz C

Chapter 12

 

Name : -----------------------------------         I.D. : -------------------       Section : --------

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  1. The following data were obtained at a certain temperature for  the reaction

 

2A (g)    +    B(g)        A2B (g)   

 

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Experiment              [A] (M)                 [B] (M)                Initial Rate (M/s)

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            1                      1.50                     1.50                         0.32

 

            2                      1.50                     2.50                         0.32

 

            3                      3.00                     1.50                         0.64

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Give the values of m, n, and k in the rate equation,   Rate = k [A] n [B] m

 

n  =   1..(1 point)     

 

m  =  0..(1 point)     

 

k  =  0.213  s-1(2 points)

 

 

 

 

 

 

 

 

 

 

2.   The decomposition of a compound is first order.  What is the half-life of this decomposition if 75 percent of a given sample of this compound decomposes in 180 min?

 

          t1/2  =   90 min(2 points)                                                                                                                                                                                                      P.T.O.

 

Quiz C (Continued)

 

  1. The rate constant of a first-order reaction is 4.60 x 10 -4 s -1 at 350 ºC.  If the activation energy is 104 kJ mol -1, calculate the temperature at which the rate constant is 7.2 x 10 -4 s -1.

 

R  =  8.314 J K -1 mol-1

 

      Temperature = 637 (or 637.2) K  OR  364 (or 364.2) ºC.(2 points)