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Radiocarbon dating is used to date a variety of sources but the main factor is that the sources would have had to once be a carbon-life form the carbon is passed through living things through the food-chain starting from the plants who breathe it in from the upper atmosphere.
Examples include: c) The half-life of carbon-14 according to my graph is about 5700-5720 years as you can see on my graph, it took 5700 years for the com to decrease from 1200 to 60 and another 5700 years for that to half into 30 cpm.
By measuring the ratio of Carbon-14 in a sample and comparing it to the amount in a recently deceased sample its date can be determined.
Tracers in medical diagnosis and industry Radioisotopes are used as tracers in industry and hospitals.
This substance is carried by the blood to the organ, eg the kidneys or the thyroid gland, that the doctor wants to examine. Tracers are chosen which will concentrate in the part of the body to be investigated, and the tracer's radiation will also be concentrated there.
Radiation detectors placed outside the body detect the radiation emitted and, with the aid of computers, build up an image of the inside of the body on a computer screen.
Over time there is a gradual decrease in the amount of Carbon-14 and the ratio of Carbon-14 atoms to other Carbon atoms declines. Therefore half of the Carbon-14 has decayed after 5730 years.
Half of the remaining Carbon-14 then decays over the next 5730 years leaving one fourth of the original amount.
In industry they can be used to: find leaks or blockages in underground pipes find the route of underground pipes track the dispersal of waste To locate a leak in an underground pipe a very small amount of radioactive material that gives off gamma rays is put into the pipe.
Since all living organisms on Earth are made up of organic molecules that contain Carbon atoms derived from the atmosphere, they therefore contain Carbon-14 atoms.