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Norman M.
Norman M., Researcher, Lecturer and Psychotherapist
Category: Home Improvement
Satisfied Customers: 2568
Experience:  ADHP(NC), ECP and UKCP Registered.
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why is the amount of carbon 14 considered a constant, since

Customer Question

why is the amount of carbon 14 considered a constant, since it decays how is is replenished?
Submitted: 3 years ago.
Category: General
Expert:  Dr. David replied 3 years ago.
Hello, this is Dr. David. I have read your question and am ready to help.

the amount of carbon 14 is not a constant.

the decay rate of carbon 14 is a constant.

carbon 14 is not replaced in a material.

is this for a class?
Customer: replied 3 years ago.

carbon 14 is in all living things because of its uptake from the air since uptahe seasis at death, and a decay of c 14 proceeds, its amount of decay lets one know the lengh of time since death, how is thelevel of c14 maintained the the living item to allow his measurement to be valid?

Expert:  Dr. David replied 3 years ago.
The uptake is not from the air

There is a small amount of carbon14 in the soil and this makes it's way into the food chain and becomes incorporated in the foods we eat and when we break down chemicals from food and incorporate the carbon14 into our bodies that is how carbon enters the body
Customer: replied 3 years ago.

ok so the c14 is taken up in food however how is the amount of c14 in any once living hing constant enough to accurately determine age by the amount on c14 decay

Expert:  Dr. David replied 3 years ago.
the age of something dead is an estimation. there is a lot of assumptions.

it assumes an average amount of C14 in the body.

C14 decays very slowly

so there is a lot of estimation of the time of death. so the dating is far from 100% perfect.

this is a good web page to read about the process

Customer: replied 3 years ago.

it may be the way i am asking the question, but we are not connecting, it maybe that this should be asked of a in the physics department, i do not know how i got into a medical section as this is my first time of asking

Expert:  Dr. David replied 3 years ago.
let me switch the question over.

please be patient and wait and don't reply
Expert:  Dr. David replied 3 years ago.
why did you give me a negative feedback?
Customer: replied 3 years ago.

i would have rated my questions on the poor side if there had been a self evaluation. you added no new information to my queastion and somehow the two of us did not seem to connect on what my question covered. so there is some c14 in the soil, which likely comes from the photosynthesis in plants, since the inseption of the earth there has been more than enough half lives of c 14 to effectively have zero left even if we started with 100%c14. since there is come left or still existing how was it replenished??

Customer: replied 3 years ago.

found the answer re c 14, nitrogen hit by cosmic radiarion in the upper atmosphere yields energy a particle and c 14, guess the % n in the atmosphere is constant enough to base a dateing technique, incidently c 14 is 1 pert per trillion even so dateing 0 to 40,000 yrs are common

Expert:  Norman M. replied 3 years ago.
Cosmic radiation in the atmosphere,will, on striking an atom, create an altered form of cosmic radiation in the form of an energetic neutron, which in turn, if it hits a nitrogen 14 atom, will form a carbon 14 atom and one hydrogen atom. Thus caerbon 14 is constantly replensished through solar radiation.

The ration of 'normal' carbon - carbon 12 - to carbon 14 in the atmosphere and in all living theings is not quite constant, but nearly so.

As soon as a living organism dies, it ceases taking in carbon, and at that point, the carbon 14 starts to decay (half-life of 5700 years) while the carbon 12 remains relatively constant.

Therefore, by comparing the ratios of carbon12 nd carbon 14 in the sample against a living specimen, the age of the sample can be determined fairly accurately
Norman M., Researcher, Lecturer and Psychotherapist
Category: General
Satisfied Customers: 2568
Experience: ADHP(NC), ECP and UKCP Registered.
Norman M. and 49 other General Specialists are ready to help you
Customer: replied 3 years ago.

i have answered you and rated you , i told you the answer before you told me. seems as though all you are looking for is a rateing of great. if that is what it takes for you to stop writing me , so be it however be informed i will be seeking answers on my own from now on as i seem to interpret my queastions more easily , and arrive at an answer sooner, bye

Expert:  Norman M. replied 3 years ago.
Glad to have been of help.

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