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cvc121
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1. Homework Statement
An iodine clock kinetics experiment was performed by varying the composition of reactant solutions and measuring resulting rates of reaction (based on the data given, I have determined the rate law to be R = [I-]1[S2O82-]1). Which of these four proposed mechanisms below would be supported by these results?
Mechanism 1: I-(aq) + I-(aq) ---> I22-(aq) (slow)
I22-(aq) + S2O82-(aq) ---> I2(aq) + SO42-(aq) (fast)
Mechanism 2: I-(aq) + S2O82-(aq) ---> [S2O82-·I]3-(aq) (slow)
[S2O82-·I]3-(aq) + I-(aq) ---> I2(aq) + 2 SO42-(aq) (fast)
Mechanism 3: I-(aq) + S2O82-(aq) <---> [S2O82-·I]3-(aq) (fast)
[S2O82-·I]3-(aq) + I-(aq) ---> I2(aq) + 2 SO42-(aq) (fast)
Mechanism 4: 2I-(aq) + S2O82-(aq) ---> I2(aq) + 2SO42-(aq)
2. Homework Equations
Rate law: R = k[A]xy
3. The Attempt at a Solution
Mechanism 1: R = [I-]2. Therefore, this is incorrect.
Mechanism 2: R = [I-][S2O82-] Therefore, this is correct.
Mechanism 3: R = [[S2O82-·I]3-][I-]. Therefore, this is incorrect.
Mechanism 4: R = [I-]2[S2O82-]. Therefore, this is incorrect.
Answer: Mechanism 2
Can anyone confirm if I am on the right track? Thanks. All help is very much appreciated.
An iodine clock kinetics experiment was performed by varying the composition of reactant solutions and measuring resulting rates of reaction (based on the data given, I have determined the rate law to be R = [I-]1[S2O82-]1). Which of these four proposed mechanisms below would be supported by these results?
Mechanism 1: I-(aq) + I-(aq) ---> I22-(aq) (slow)
I22-(aq) + S2O82-(aq) ---> I2(aq) + SO42-(aq) (fast)
Mechanism 2: I-(aq) + S2O82-(aq) ---> [S2O82-·I]3-(aq) (slow)
[S2O82-·I]3-(aq) + I-(aq) ---> I2(aq) + 2 SO42-(aq) (fast)
Mechanism 3: I-(aq) + S2O82-(aq) <---> [S2O82-·I]3-(aq) (fast)
[S2O82-·I]3-(aq) + I-(aq) ---> I2(aq) + 2 SO42-(aq) (fast)
Mechanism 4: 2I-(aq) + S2O82-(aq) ---> I2(aq) + 2SO42-(aq)
2. Homework Equations
Rate law: R = k[A]xy
3. The Attempt at a Solution
Mechanism 1: R = [I-]2. Therefore, this is incorrect.
Mechanism 2: R = [I-][S2O82-] Therefore, this is correct.
Mechanism 3: R = [[S2O82-·I]3-][I-]. Therefore, this is incorrect.
Mechanism 4: R = [I-]2[S2O82-]. Therefore, this is incorrect.
Answer: Mechanism 2
Can anyone confirm if I am on the right track? Thanks. All help is very much appreciated.
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