Which isotope is commonly used to date decayed organic matter?

Answer 1

A well-known method is C-14 dating. Carbon 14 is a radioactive isotope of carbon that has half-life of 5730 years, meaning that if you start with 1000 g of C-14, after 5730 years you would have 500 g left (the other half has decayed into N-14). C-14 is present in trace amounts in nature and living organisms would therefore maintain a near-constant level of C-14 in their bodies if they consume and interact with their surroundings. Dead organisms, however, can no longer eat and therefore cannot replenish their C-14 levels, and the C-14 levels would begin to fall due to decay. The amount of C-14 in a dead organism can be compared to a reference level to determine how much time has passed since it died by the formula T = -5730*log2(r/R) where T is the time since the organism's death, r is the remaining level of C-14, and R is the reference level of C-14.

Answer 2

All living things contain carbon, which we all accumulate from our food and from the air. That's true for birds, animals, trees, people; if it's alive, it is bringing in carbon from the environment. When we die, or when a tree dies, we stop taking in carbon from the environment.

Carbon is an element which has 6 protons in the nucleus, and some number of neutrons. The most prevalent are 6 or 7 neutrons, making Carbon either a 12 or 13 mass atom.

There are also several radioactive isotopes, the longest-lived version having 8 neutrons. This carbon-14 isotope decays with a half-life of 5,715 years, and turning into nitrogen. When we breathe in, or eat anything, we're adding a tiny bit of carbon-14 to our bodies - but when we die, this stops.

We know the ratio of normal carbon to carbon-14 in the environment. So if we carefully measure the amount of carbon-12 to carbon-14 in an ancient body, or an ancient tree, we can calculate at least approximately how long it has been since any new c-14 was added; that is, how long it has been dead.

Answer 3

Carbon-14 is commonly used to date decayed organic matter. This isotope is formed in the atmosphere and taken in by living organisms during their lifetime. As the organism decays, the amount of Carbon-14 in its remains decreases over time, allowing scientists to determine its age.

Answer 4

1. C-14 and C-12

because g is organic, compound

Answer 5

Carbon 14