Vocabulary | |
half life first order reaction integrated rate law rate constant |
where [A] is the concentration of radium-223 at time t and k is the rate constant (0.0606 day-1). You want to calculate the time it takes for the concentration to fall from [A]0 to ½[A]0. The rate law will have to be integrated.
Rearrange the equation so that all concentration dependent terms are collected on one side, and all time dependent terms are on the other:
Integrating from time 0 to time t,
the first order integrated rate equation is
The half life is the time required for the concentration to drop to one-half its original value. We can write
and solving for the half life,
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