Question

Rate Law: Iodination of Acetone

Experiment X
trial   initial [A]	initial [B]	Rate (M/s)
#1    1.00 x 10-3	0.25 x 10-3	0.26 x 10-9
#2   1.00 x 10-3	0.50 x 10-3	0.52 x 10-9
#3   1.00 x 10-3	1.00 x 10-3	1.04 x 10-9
#4    2.00 x 10-3	1.00 x 10-3	4.16 x 10-9
#5    3.00 x 10-3	1.00 x 10-3	9.36 x 10-9
#6    4.00 x 10-3	1.00 x 10-3	16.64 x 10-9

Determine the rate law and calculate the rate constant for the data given for experiment X .

1. Rate Law

2. Rate constant

The following data are for Questions 3 through 5 and refer to the reaction:

         NO₂(g) + CO(g)à NO(g) + CO₂(g)                   

All data were taken at 225.0°C.

Trial	initial [NO2]	initial [CO]	Initial Rate M/s
#1 #2 #3	0.263 0.263 0.526	0..826 0.413 0.413	1.44X10-5     1.44X10-5    5.76   X10-5

3. What is the law for the reaction?

4. Calculate the value of the rate constant at 225°C.

5. Calculate the rate of appearance of CO₂ when [NO₂] =[CO] = 0.500M

The times listed in the following table are those required for the concentration of S₂O₈^-2 to decrease by 0.00050 M as measured in an “iodine clock” reaction at 23°C. What is the rate law?

                 

Iodine clock reaction	The net reaction is: S2O8-2 + 2 I- → I2 + 2 SO4-2
Trial	Initial [S2O82-]	initial [I-]	Time (sec)
#1	0.0400	0.080	39
#2	0.0400	0.040	78
#3	0.0100	0.080	156
#4	0.0200	0.020	312

6. What is the rate law for the ““iodine clock” in the reaction above?

7 . What is the rate constant the“iodine clock” ?

Write the rate laws and determine the units of the rate constant by using the units M for concentration and s for time) for the following reactions:

8. The reaction of oxygen atoms with NO₂ is first order in both reactants

àRate law=

àunits

9. The reaction between NO and Cl₂ is second order in NO and first order in Cl₂

àRate law=

àunits

10 the reaction between Cl₂ and chloroform(CHCl₃) is first order in CHCl₃ and one-half in Cl₂

àRate law=

àunits

Answer 1