Radio carbon dating chemistry

Mass spectrometers detect atoms of specific elements according to their atomic weights.

They, however, do not have the sensitivity to distinguish atomic isobars (atoms of different elements that have the same atomic weight, such as in the case of carbon 14 and nitrogen 14—the most common isotope of nitrogen).

Thanks to nuclear physics, mass spectrometers have been fine-tuned to separate a rare isotope from an abundant neighboring mass, and accelerator mass spectrometry was born.

A method has finally been developed to detect carbon 14 in a given sample and ignore the more abundant isotopes that swamp the carbon 14 signal.

Reference materials are also pressed on metal discs.

These metal discs are then mounted on a target wheel so they can be analyzed in sequence.

In mass analysis, a magnetic field is applied to these moving charged particles, which causes the particles to deflect from the path they are traveling.

The negatively charged carbon atoms, however, move on to the stripper (a gas or a metal foil) where they lose the electrons and emerge as the triple, positively charged carbon atoms.

There are two techniques in measuring radiocarbon in samples—through radiometric dating and by Accelerator Mass Spectrometry (AMS).

The two techniques are used primarily in determining carbon 14 content of archaeological artifacts and geological samples.

An accelerator mass spectrometer, although a powerful tool, is also a costly one.

Establishing and maintaining an accelerator mass spectrometer costs millions of dollars.

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