Isotope 14 of carbon, what is it, and how does it works?

Question

I have this assignment where they ask me what is this Isotope, what do humans use it for, a how does it work
Carbon, isotope 14

Answer 1

Joker gives a pretty good answer; though be it cut and paste, not that there is anything wrong with that.
I would just like to bring to your attention that Carbon 14 dating is by no means accurate!
"Dr. Libby, the discoverer of the C14 method, which won for him a Nobel prize, expressed his shock that human artifacts extended back only 5000 years, a finding totally in conflict with any evolutionary concept. Older dates were found to be very unreliable (CRSQ , 1972, 9:3, p.157). By this time tens of thousands of C14 dates have been published from tests performed by various laboratories around the world. In the annual volumes in which the dates are published, concerns have been expressed about many relatively young dates that violate established geological age notions. One example given was Ice-Age materials that were dated by C14 to fall within the Christian era (CRSQ , 1969, 6:2, p.114). In his book on prehistoric America, Ceram notes a classic case of the difficulties that befall C14 dating. Bones 30,000 years old were found lying above wood dated at 16,000 years (Ceram, 1971, p.257-259). "
Take a look at this dinosaur bone (Illium bone of an Acrocanthosarus) dated at 19,000 years old.
http://www.bible.ca/tracks/dating-acrocanthosarus-illium-bone.jpg
Take a look at the source web site. On that page if you scroll down a bit it will give you a list of carbon 14 as well at other dating methods possibly worth mentioning in your assignment. Have fun!

Answer 2

Carbon 14 is a naturally occuring isotope of Carbon. It has six protons and eight neutrons in its nucleus. C14 occurs in the atmosphere when cosmic rays hit nitrogen. Since this isotope has a half life of 5730 years, any living organism that dies has a progressively smaller amount of C14 in it, as that C14 decays away. So humans "use" C14 as a way to determine the age of dead organic matter, such as wood from a prehistoric campfire, or from the bones of a long dead animal, like a mastadon found in the frozen tundra, etc. If 1/8 of the original amount of C14 remains, then the item is 3 x 5730 years old = 17,200 years.
( 1/8 = 1/2 x 1/2 x 1/2 so this is 3 "half lives" of C14)

Look up more in Wikipedia in the link below - it's a good article.

OC

Answer 3

Carbon-14, 14C, or radiocarbon, is a radioactive isotope of carbon discovered on February 27, 1940, by Martin Kamen and Sam Ruben. Its nucleus contains 6 protons and 8 neutrons. Its presence in organic materials is used extensively as basis of the radiocarbon dating method to date archaeological, geological, and hydrogeological samples.

It occurs naturally and has a relative abundance up to 1 part per trillion (0.0000000001%) of all naturally-occurring carbon on Earth. The half-life of carbon-14 is 5730±40 years. It decays into nitrogen-14 through beta-decay.[1] The activity of modern standard radiocarbon is about 14 disintegrations per minute (dpm) per gram carbon (ca. 230 mBq/g).

Carbon-14 is produced in the upper layers of the troposphere and the stratosphere by thermal neutrons absorbed by nitrogen atoms. When cosmic rays enter the atmosphere, they undergo various transformations, including the production of neutrons. The resulting neutrons participate in the following reaction:

n + 14N → 14C + 1H

The highest rate of carbon-14 production takes place at altitudes of 9 to 15 km (30,000 to 50,000 feet), and at high geomagnetic latitudes, but the carbon-14 readily mixes and becomes evenly distributed throughout the atmosphere and reacts with oxygen to form radioactive carbon dioxide. Carbon dioxide also dissolves in water and thus permeates the oceans.

Carbon-14 can also be produced in ice by fast neutrons causing spallation reactions in oxygen.

Most of man-made chemicals are made of fossil fuels, such as petroleum or coal, in which the carbon-14 has long since decayed. Presence of carbon-14 in the isotopic signature of a sample of carbonaceous material therefore indicates its possible biogenic origin and relatively recent geologic age.

Answer 4

Google is your friend, DH.