How long must a sample be irradiated before all 59-Co atoms are converted to 60-Co? [closed]








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For the interaction, n$^0$ + $^{59}$Co $\to$ $^{60}$Co




At a constant neutron flux, this is a first-order reaction:


$ - \frac{{{\text{d}}\left[ {{}^{59}{\text{Co}}} \right]}}{{{\text{d}}t}} = k \cdot \left[ {{}^{59}{\text{Co}}} \right]$


$\left[ {{}^{59}{\text{Co}}} \right] = {\left[ {{}^{59}{\text{Co}}} \right]\_0} \cdot {\operatorname{e} ^{ - k \cdot t}}$


Theoretically, $\left[ {{}^{59}{\text{Co}}} \right]$ will never become zero.


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