The unstable carbon-14 gradually decays to carbon-12 at a steady rate. And thats the key to radiocarbon dating. Scientists measure the ratio of carbon isotopes to be able to estimate how far back in time a biological sample was active or alive.

## How is carbon-14 used to date?

The Carbon 14 (C-14) dating method is a radiometric dating method. A radiometric dating uses the known rate of decay of radioactive isotopes to date an object. Each radioactive isotope has a known, fixed rate of decay, which we call a half-life. Once C-14 is produced, it starts to decay back to nitrogen.

Carbon 14 is a common form of carbon which decays over time. The amount of Carbon 14 contained in a preserved plant is modeled by the equation f(t) = 10e^{-ct}.

## What is the charge for carbon-14?

Because carbon-14 has six protons, it is still carbon, but the two extra neutrons make the nucleus unstable. In order to reach a more stable state, carbon-14 releases a negatively charged particle from its nucleus that turns one of the neutrons into a proton.