One of the battles fought in the scientific community today is the dispute over how old the earth is. One side, the Creationists, say the earth is from 6-10 thousand years old. Contrary to this, the Evolutionists claim that it is actually millions to billions of years old. A method that both groups use, though, to aid in their statements is radiometric dating, particularly by using Carbon-14 (14C).
The atom Carbon-14 (14C) is an isotope of the carbon (12C) element. Basically stated, an isotope is an atom that has a different number of neutrons and/or protons than electrons. For instance, the common form of carbon is carbon-12 (12C). The number 12 in the superscript means the sum of protons and neutrons in the atom. So, since carbon had six electrons, and also since there are nominally the same number of protons in an atom as electrons, it is predicted that there are six neutrons (six electrons means there are six protons, so then twelve minus six means that there are also six neutrons).
Carbon-14 (14C) is formed when rays from space collide with atoms in the upper atmosphere and cause some of the neutrons to separate and fall downward. These then crash into common nitrogen atoms (14N) and cause it to loose one electron, thus making six electrons, seven protons, and seven neutrons; or carbon-14 (14C). It then mixes with two oxygen atoms (O2) to form 14CO2, which, like regular carbon dioxide (CO2), is taken in by people, animals, plants, etc.
The problem is that carbon-14 is constantly changing back to nitrogen, and this unstableness makes it radioactive. However, once it changes, it is replaced by more carbon-14 atoms in the air. So then the ratio of 14C/12C is usually the same in living things as in the atmosphere. With this in mind, I will now go on to how the carbon ‘clock’ works.
Once a living thing dies, it stops the intake of carbon atoms to replace to decaying carbon-14 in it. This is how the ‘clock’ starts ticking. It takes 5,730 +/- 40 years for half of any amount of carbon-14 to convert to nitrogen. This is known as a ‘half life’ because half of it’s ‘life’ has passed. So in order to determine the age of specimen, you need to measure the amount of 14C/14N present in it and figure out what the percent of 14N is. Thus, if the percent is around 50% then the thing has been dead for around 5,730 years, and 75% of nitrogen would be around 11,460 years old (since 50% is 5,730 years so then half of that (75%) would be another 5,730 years).
So that is the basics on how carbon-14 radiometric dating works. In the next issue, I’ll go into some of the faults with this, and how it actually might give more evidence for a young earth than one that’s ‘millions’ or ‘billions’ of years old.
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