How do archaeologists use c-14-1?
1 Answer
They use it to measure the age of organic material up to 50,000 years old
Explanation:
C-14 is the only radioactive isotope of carbon, and as such it has a half-life . That half-life has been measured to be about 5,730 years, and the subsequent half-lifes( quarter, eighth, etc.) have been measured up to 50,000 years old.
C-14 is also found in all organic material on Earth, which means if we have a fossil that is less then 50,000 years old, we can accurately measure its age by counting the amount of C-14 atoms still present. Because the measurement is atomic, physical and chemical changes do not affect the levels, which radiocarbon dating (the official term) a great tool for archaeologists.
There are a few hurdles to get over to reliably measure C-14, though. The first is that the levels of C-14 over the years have increased and decreased. To get over that, scientists have measured the levels of C-14 in the atmosphere thousands of years ago by studying numerous tree rings and their C-14 levels.
Another problem is that C-14 only makes up 0.0000000001% of organic material and our atmosphere, meaning large samples of objects are needed for reliable measurements. To get around that, researches use Accelerator Mass Spectrometers , which are able to reduce the size of samples needed to only 1 gram.
Contamination can be a hassle too: If the sample is not thoruoughly cleaned, the measurements may be off and thus useless.
http://www.abc.net.au/science/articles/2010/12/09/3088319.htm
I hope I helped!
