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Example Questions
Example Question #411 : Ap Physics 2
If an unknown compound undergoes radioactive decay such that decays in , what is the rate constant for this reaction?
In this question, we're told that a radioactive compound is decaying, and we're asked to determine the rate constant for the process.
Because radioactive decay reactions are first-order, we can use the first-order reaction equation.
Rearranging this expression, we can isolate the rate constant term, , as follows.
Now, we can plug in the values that were given to us in the question stem to calculate the answer.
Example Question #412 : Ap Physics 2
If it takes a radioactive compound for of it to decay, what is this reaction's rate constant?
In this question, we're told that a radioactive compound has decayed by a certain amount in a given amount of time. We're asked to find the rate constant.
First, we have to recognize that all radioactive decay reactions follow first-order kinetics. Hence, we can use the first-order rate equation to solve this question.
Because we're told that of the compound has decayed, we know there must be of it left at the mark.
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