**I am confused about integrated rate reactions and half life problems. For example: The first order rate constant for the radioactive decay of radium-223 is 0.0606/day. what is the half life of radium-223?**

Tara 02/05/99-

The rate law for this first order rate equation is**Vocabulary**half life

first order reaction

integrated rate law

rate constant

*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:

*t*,The

**half life**is the time required for the concentration to drop to one-half its original value. We can write

General Chemistry Online! How can I compute the half-life of a first order reaction?

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