Consider the following reaction:
At 25°C, the following two experiments were run, yielding the following data:
Experiment 1: [Y]0 = 3.0 M
[CH3X] (mol/L) | Time(h) |
7.08 × 10−3 | 1.0 |
4.52 × 10−3 | 1.5 |
2.23 × 10−3 | 2.3 |
4.76 × 10−4 | 4.0 |
8.44 × l0−5 | 5.7 |
2.75 × l0−5 | 7.0 |
Experiment 2: [Y]0 = 4.5 M
[CH3X] (mol/L) | Time(h) |
4.50 × 10−3 | 0 |
1.70 × 10−3 | 1.0 |
4.19 × 10−4 | 2.5 |
1.11 × 10−4 | 4.0 |
2.81 × l0−5 | 5.5 |
Experiments also were run at 85°C. The value of the rate constant at 85°C was found to be 7.88 × 108 (with the time in units of hours), where [CH3X]0 = 1.0 × 10−2 M and [Y]0 = 3.0 M.
a. Determine the rate law and the value of k for this reaction at 25°C.
b. Determine the half-life at 85°C.
c. Determine Ea for the reaction.
d. Given that the C8X bond energy is known to be about 325 kJ/mol, suggest a mechanism that explains the results in parts a and c.
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Chemistry: An Atoms First Approach
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