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. But the question is, when does an atom or nucleus decide to decay? So it could either be beta decay, which would release electrons from the neutrons and turn them into protons. And normally when we have any small amount of any element, we really have huge amounts of atoms of that element. That's 6.02 times 10 to the 23rd carbon-12 atoms. This is more than we can, than my head can really grasp around how large of a number this is. Let's say I have a bunch of, let's say these are all atoms. And let's say we're talking about the type of decay where an atom turns into another atom. Or maybe positron emission turning protons into neutrons. And we've talked about moles and, you know, one gram of carbon-12-- I'm sorry, 12 grams-- 12 grams of carbon-12 has one mole of carbon-12 in it.
To determine the age of a sample, the SCAR technique uses a highly stable infrared laser to excite carbon dioxide molecules in a mirrored cavity.
When the laser is turned off, trapped light dies away in the cavity (or “rings-down”) at a rate that depends on the amount of carbon-For a date, give me a ring.
I know can be hard to wrap your head around, so let's model it with a six-sided die. You can use Lego bricks, pennies, beans—anything you can easily count. Every time you roll a one, put that object into a separate pile.
Count the remaining objects and repeat the process until half of them have decayed. It took a while, but we finally got pretty close to 40 tiles left.
a bad rap, what with radiation and fallout and nuclear waste and all. One of the coolest (OK, maybe the coolest) is using radioactive carbon to determine the age of old bones or plants.
To understand this, you must first understand radioactivity and decay.Carbon-14 has a half-life of 5,730 ± 40 years— during the succeeding 5,730 years.Because carbon-14 decays at this constant rate, an estimate of the date at which an organism died can be made by measuring the amount of its residual radiocarbon.Carbon dating uses an unstable isotope of carbon to find the date of dead substances.This isotope Carbon-14 has a half life of 5,700 years.When the laser is turned off, trapped light dies away in the cavity (or “rings-down”) at a rate that depends on the amount of carbon-A new optics-based method for detecting trace gases could offer a potential alternative way to date archeological artifacts.