There are several isotopes of the element carbon.
Compare two different isotopes of carbon, such as Carbon-12 and Carbon-14.
A researcher wants to find the half-life of a radioactive isotope of carbon. They measure the count rate of a sample. Describe how they could correct the measured count rate for background radiation.
The researcher measures the corrected count rate every 25 seconds. The table shows the results obtained:
Time (seconds)Corrected count rate (counts per second)080255750407528100201251415010\begin{array}{|c|c|} \hline \text{Time (seconds)} & \text{Corrected count rate (counts per second)} \\ \hline 0 & 80 \\ \hline 25 & 57 \\ \hline 50 & 40 \\ \hline 75 & 28 \\ \hline 100 & 20 \\ \hline 125 & 14 \\ \hline 150 & 10 \\ \hline \end{array}Time (seconds)0255075100125150Corrected count rate (counts per second)80574028201410Use the data in the table to estimate the half-life of this isotope. Explain your method clearly.
