Uses radioisotopes carbon dating
One excellent example of this is the use of radioactive carbon-14 to determine the steps involved in the photosynthesis in plants.
We know these steps because researchers followed the progress of the radioactive carbon-14 throughout the process.
Once a living thing dies, however, it no longer acquires carbon-14, and as time passes, the carbon-14 that was in the tissues decays.
The half-life of a radioactive isotope describes the amount of time that it takes half of the isotope in a sample to decay.(Recall that tritium, H, is a radioactive isotope of hydrogen.) Tracers can also be used to follow the steps of a complex chemical reaction.After incorporating radioactive atoms into reactant molecules, scientists can track where the atoms go by following their radioactivity.When finding the age of an organic organism we need to consider the half-life of carbon 14 as well as the rate of decay, which is –0.693.
For example, say a fossil is found that has 35% carbon 14 compared to the living sample. We can use a formula for carbon 14 dating to find the answer.
Where t is the age of the fossil (or the date of death) and ln() is the natural logarithm function.