# Describe how carbon 14 is used as a dating method dating customs of italy

By comparing the surviving amount of carbon-14 to the original amount, scientists can calculate how long ago the animal died.

Since the atmosphere is composed of about 78% nitrogen,2 a lot of radiocarbon atoms are produced—in total about 16.5 pounds (7.5 kg) per year.

These excited neutrons then collide with nitrogen atoms in the atmosphere, changing them into radioactive carbon-14 atoms.

CARBON-14 IS ABSORBED (Figure 1b): Plants absorb this carbon-14 during photosynthesis.

Instead, the radiocarbon atoms in their bodies slowly decay away, so the ratio of carbon-14 atoms to regular carbon atoms will steadily decrease over time (Figure 1c).

Let’s suppose we find a mammoth’s skull and we want to date it to determine how long ago it lived.

The radiocarbon half-life or decay rate has been determined at 5,730 years.

Next comes the question of how scientists use this knowledge to date things.

The carbon-14 in their bodies breaks down to nitrogen-14 and escapes at the same rate as new carbon-14 is added. CARBON-14 IS DEPLETED (Figure 1c): When an animal dies the carbon-14 continues to break down to nitrogen-14 and escapes, while no new carbon-14 is added.Many people assume that rocks are dated at “millions of years” based on radiocarbon (carbon-14) dating. The most well-known of all the radiometric dating methods is radiocarbon dating. Carbon-14 can yield dates of only “thousands of years” before it all breaks down.Since each beta particle represents one decayed carbon-14 atom, we know how many carbon-14 atoms decay during a month.Chemists have already determined how many atoms are in a given mass of each element, such as carbon.4 So if we weigh a lump of carbon, we can calculate how many carbon atoms are in it.