Noun
carbon-14- a radioactive isotopes of carbon, ; it is used in radiocarbon dating
Read full definition at wiktionary.org
...Carbon-14, 14C, or radiocarbon, is a radioactive isotope of carbon discovered on February 27, 1940, by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley, though its existence had been suggested already in 1934 by Franz Kurie. Its nucleus contains 6 protons and 8 neutrons. Its presence in organic materials is the basis of the radiocarbon dating method to date archaeological, geological, and hydrogeological samples. Read full entry
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- 1.Carbon-14 - Wikipedia, the free encyclopedia
- The half-life of carbon-14 is 5,730±40 years. ... Carbon-14 can also be produced in ice by fast neutrons causing spallation reactions in oxygen. ...
- http://en.wikipedia.org/wiki/C
arbon-14
- 2.carbon 14: Definition from Answers.com
- carbon 14 n. A naturally radioactive carbon isotope with atomic mass 14 and half-life 5,730 years, used in determining the age of ancient organic,
- http://www.answers.com/topic/c
arbon-14
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Carbon-14?
I have a few questions about
carbon 14.
1. How does it decay and
establish a small constant
level in the atmosphere?
2. How does that level
establish in plants?
3. How does this level
esablish in animals?
4. How is carbon-14
significant in death?
5. How can a geiger counter be
used to age an artifact?
If you could answer these it
is much appreciated.
Thank-you!!!
If you answer any of the
questions note which one you
are answering please.
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1. C14 is constantly being created in the upper atmosphere by nitrogen absorbing a neutron (see reference for details). This creation of c14 in the upper atmosphere balances the decay of c14. 2 C14 is taken into plant via respiration as co2, it is then used throughout the plant as if it were c12. 3. Animals eat the plants and the c14 in the plant is incorporated into the animal in the same way that carbon 12 is used within the animal. 4. Since c14 is only taken in through respiration (in plants) and feeding (in animals) then uptake of c14 stops at the death of the organism. 5. The half-life of a radioactive substance is how long it will take for half the atoms in a sample to decay. After 1 half-life then the sample will be half as radioactive, after 2 half-lives it will be only a quarter as radioactive. Since we know that uptake of c14 stops at the death of the organism we can measure the radioactivity of the sample, compare it to the base line and be able to say how many half-lives ago the organism died, since each compound has a fixed half-life it is simple to convert half-lives to years. In the case of artifacts many artifacts contain organic materials, eg leather, wood or are found in situ with organic residues and so can be carbon dated. |
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Carbon 14?
Carbon-14 is produced in the
upper atmosphere by action of
cosmic rays. Once the C 14 has
been formed, by converting
nitrogen-14 into carbon-14, it
behaves like ordinary
carbon-12, combining with
oxygen to give carbon dioxide,
and freely cycling through the
cells of all plants and
animals. Carbon-14 is used for
a dating material because once
it has been formed, C14 begins
to decay radioactively back to
nitrogen-14, at a rate of
change that can be measured.
As soon as an organism dies,
the C14 atoms which decay are
no longer replaced by new ones
through respiration.
Consequently, the ratio of C14
to C12 in that once-living
organism decreases as time
goes on. The problem with the
carbon dating method is
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While the information on this is great, as Christians we are called to be shining examples to all. We are to obey the laws of the land, and here in Yahoo Answers, the law of the land is the community guidelines, which clearly state that you MUST ask a question. For this I must report you. I wanted to also add that the phenomenon with C14 and water is not just reserved to aquatic animals. It has been shown that C14 is water soluble, and if something dead is pulled from the water the C14/C12 ratio will be off, even after a short time. I believe animals that died in the flood would qualify. It should also be noted that archeologists find C14 dating the least reliable method of dating. If they find a skeleton with a certain piece of pottery, for example, and the skeleton dates too old for what they believe is reasonable for the pottery they will reject the C14 date of the skeleton. |
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Can carbon-14 dating be used I need to know this for
physics. I know carbon 14
dating can be used to measure
the age of human and animal
remains, but stone objects i'm
not sure about. A little
explanation would be great.
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Carbon dating works becuase we can calculate the decay of carbon 14 in organic matter. Carbon 14 is produced in reactions in the upper atmosphere, and stays at relatively constant levels. This carbon 14 acts just like normal carbon (except it is radioactive of course!) and is absorbed into the body. When someone dies the carbon 14 is no longer replenished, and the radioactivity will decay exponentially towards zero. Since a stone wall is unlikely to be able to absorb carbon 14 you wont be able to date its age using this technique. |
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