# Type radiation used carbon dating

Carbon-14 dating is a way of determining the age of certain archeological artifacts of a biological origin up to about 50,000 years old.

At any given moment, for a certain type of element or a certain type of isotope of an element, there's some probability that one of them will decay. If I wait carbon-14's half-life-- this is a specific isotope of carbon. So when you have the same element with varying number of neutrons, that's an isotope. Let's think about what happens after another half-life. And by the law of large numbers, half of them will have converted into nitrogen-14. This might be the one ultra-stable nucleus that just happened to, kind of, go against the odds and stay carbon-14.

And so, like everything in chemistry, and a lot of what we're starting to deal with in physics and quantum mechanics, everything is probabilistic. So one of the neutrons must have turned into a proton and that is what happened. And you might say, oh OK, so maybe-- let's see, let me make nitrogen magenta, right there-- so you might say, OK, maybe that half turns into nitrogen. And over 5,740 years, you determine that there's a 50% chance that any one of these carbon atoms will turn into a nitrogen atom. And we could keep going further into the future, and after every half-life, 5,740 years, we will have half of the carbon that we started. Now, if you look at it over a huge number of atoms. But after two more years, how many are we going to have? So this is t equals 3 I'm sorry, this is t equals 4 years.

And maybe not carbon-12, maybe we're talking about carbon-14 or something. And then nothing happens for a long time, a long time, and all of a sudden two more guys decay. And the atomic number defines the carbon, because it has six protons. If they say that it's half-life is 5,740 years, that means that if on day one we start off with 10 grams of pure carbon-14, after 5,740 years, half of this will have turned into nitrogen-14, by beta decay. What happens over that 5,740 years is that, probabilistically, some of these guys just start turning into nitrogen randomly, at random points. So if we go to another half-life, if we go another half-life from there, I had five grams of carbon-14. So now we have seven and a half grams of nitrogen-14. This exact atom, you just know that it had a 50% chance of turning into a nitrogen.

If you were using a geiger-type counter (which can't determine the energy or type of radiation) to determine the sample's radioactivity, then absolutely any other ionizing radiation would trigger the detector and prevent an accurate age determination.

I'm not sure, to be honest, but I assume typically a spectroscopic detector is used for C-14 dating.