Problem: Molecular iodine, I2(g), dissociates into iodine atoms at 625 K with a first-order rate constant of 0.271 s-1 .If you start with 0.055 M of I2 at this temperature, how much will remain after 2.56 s assuming that the iodine atoms do not recombine to form I2?

FREE Expert Solution
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FREE Expert Solution

We’re given the following first order reaction:

I2(g)  2 I(g); k = 0.271 s–1


The integrated rate law for a first order reaction is as follows:



where [A]t = concentration at time t, k = rate constant, t = time, [A]0 = initial concentration. We’re being asked to calculate the amount of I2 remaining after 2.56 s if we start with 0.055 M I2.


This means we have:

[I2]0 = 0.055 M          k = 0.271 s–1

[I2]t = ?                      t = 2.56 s


86% (140 ratings)
Problem Details

Molecular iodine, I2(g), dissociates into iodine atoms at 625 K with a first-order rate constant of 0.271 s-1 .

If you start with 0.055 M of I2 at this temperature, how much will remain after 2.56 s assuming that the iodine atoms do not recombine to form I2?

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