So you might get a question like, I start with, oh I don't know, let's say I start with 80 grams of something with, let's just call it x, and it has a half-life of two years.
So what we do is we come up with terms that help us get our head around this. So I wrote a decay reaction right here, where you have carbon-14. So now you have, after one half-life-- So let's ignore this. I don't know which half, but half of them will turn into it. And then let's say we go into a time machine and we look back at our sample, and let's say we only have 10 grams of our sample left.
This means that this new type of dating can reach much farther back in time.
Theoretically, this method could be used to date ice that is 1.5 million years old.
The amount of decay in krypton’s radioactive isotope krypton-81 can be calculated in a process called radiometric krypton dating.
Krypton dating is slightly different from carbon dating, since the half life of krypton is 230,000 years – about 5x that of carbon.
Therefore, for the record, I attend fourteen churches, I drive my car 337,000 miles a year for business purposes, and my company spent $127 million dollars on new equipment...
SAL: In the last video we saw all sorts of different types of isotopes of atoms experiencing radioactive decay and turning into other atoms or releasing different types of particles.
Clay Jones steps in for Jason as we interview Alan Levinovitz.
Alan Levinovitz is an assistant professor of Chinese philosophy and religion at James Madison University and author of The Gluten Lie: And Other Myths About What You Eat.
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.
In addition to a lengthier half life, the krypton dating is more stable than carbon dating. (National Geographic) To examine the krypton that was trapped in the air bubbles of the Antarctic ice, 660 pounds of cylindrical ice samples were removed by researchers, placed in vacuums, and melted to unlock the ancient air.