Correct me if I'm wrong, but if you have an amount of Carbon-14, it will decay at a constant rate. How can someone determine the age of something without knowing the starting amount of Carbon-14? If they are just guessing at the starting amount, by the transitive property wouldn't they just be guessing the age?
2006-12-30 13:58:25 · 5 answers · asked by nathan_b37 2 in Science & Mathematics ➔ Chemistry
It is the ratio, but your question is still apt. Was the ratio of carbon12 to carbon14 essentially the same over the timescale we use carbon dating?
As far as we can tell it was. This is checked by looking at other dating methods and comparing the results to what you get with carbon dating. For instance, tree ring data goes back 5000 or so years, then you have tree rings that overlap with sediments that are layered and have organics that you can test with carbon dating.
So, it's not just a theory without supporting evidence. There is good reason to believe that the ratio of C12 to C14 remains the same over the time periods in question to the accuracy we give for the test.
2006-12-30 14:12:14 · answer #1 · answered by xaviar_onasis 5 · 0⤊ 0⤋
The ratio of C14 and C12 in the atmosphere is constant. Since living organisms (specifically plants which are taking up carbon dioxide from the atmosphere) do not discriminate between C14 and C12, the ratio of C14 in the plant tissue is the same as it is in the atmosphere. Any organism that eat the plants will also have the same C14 ratios.
Once the organism dies, the C14 decays, so the ratio of C14 to C12 will change over time. This is how scientists can figure out the age of dead organic stuff using C14 method.
By the way, I was listening to a pod cast that was taking about the fact that different plants actually DO use C14 differently. I don't remember the details, but something about difference between C4 plants and C3 plants (or was it CAM plants... ). And since animals that eat these plants will have the same C14 ratio as the plants they ate, they can track the annual dietary changes of animals (in this case homonids) by looking at the changes in C14 in the annual rings of bones or teeth or something... (sorry I don't have the details). So these ancient people moved around and ate different types of plants, and the record of that was layed down in their teeth, and now scientists can study that. Amazing!
2006-12-30 14:18:13 · answer #2 · answered by Ms. K. 3 · 0⤊ 1⤋
living issues take up a undeniable quantity of Carbon-14, it somewhat is volatile. What which potential is that when it dies, the quantity of the carbon-14 starts off to bypass away at a nil.5 existence of 5400 years. which potential, after 5400 years a lifeless difficulty has 0.5 the Carbon-14 then something living. After 10,800 years, 1 / 4 of the C-14 is left etc. it somewhat is a geometrical regression, and it works to age something to approximately 60,000 years.
2016-10-19 06:19:32 · answer #3 · answered by Anonymous · 0⤊ 0⤋
No, I think there is a way to do it back wards. By seeing something about carbon in the object. U can also guess. I believe.
2006-12-30 14:02:18 · answer #4 · answered by Best Helper 4 · 0⤊ 0⤋
you don't need to know the amount, you just need to know the ratio of carbon 14 to carbon 12, it isn't dependent on the amount
2006-12-30 14:04:43 · answer #5 · answered by Nick F 6 · 0⤊ 0⤋