How does “Carbon Dating” work?
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It’s first important to note that carbon dating is something done on things that were alive and are now dead. Specifically. There are other radio dating techniques for minerals, and there are other techniques for dating really old but alive creatures.
There’s a constant process in which nitrogen in the atmosphere is converted into Carbon 14, which then can combine with oxygen to form carbon dioxide. Normally carbon has 6 protons and 6 neutrons (for a total of 12, Carbon 12). Carbon 14 has 8 neutrons. This C14 CO2 is absorbed by plants as normal, and integrated into their structure. When animals eat the plants, they use their carbon fir themselves as well. So this C14 will be carried through.
The important thing here is that the amount of C14 to C12 is a known ratio. And the amount of it in the bodies of plants and animals when alive will be the about the same (with some known caveats) as the atmospheric ratio. So you know how much the living being should have had when they were alive.
Now, the next thing is that C14 is radioactive. It decays. And the half live (how long it takes for half of it to disappear) is 5730 years.
So you know how much C14 a sample should have had. We can measure how much C14 it actually has. Because we know the decay rate, we can fairly accurately tell how long it would have taken for the missing amount to disappear. We now know how long ago the creature died.
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