A certain first-order reaction is 27.5 percent complete in 8.90 min at 25°C. What is its rate constant?

Explanation:

Hello there!

In this case, according to the given information, it turns out necessary for us remember that the first-order kinetics is given by:

Whereas the 27.5% complete means A/Ao=0.275, and thus, we solve for the rate constant as follows:

Then, we plug in the variables to obtain:

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