Geologists do not use carbon-based radiometric dating to determine the age of rocks. Carbon dating only works for objects that are younger than about 50,000 years, and most rocks of interest are older than that. Over time, carbon-14 decays radioactively and turns into nitrogen.

## How reliable is carbon-14 dating?

To radiocarbon date an organic material, a scientist can measure the ratio of remaining Carbon-14 to the unchanged Carbon-12 to see how long it has been since the materials source died. Advancing technology has allowed radiocarbon dating to become accurate to within just a few decades in many cases.

## How long does carbon-14 take to decay?

5,730 years The time it takes for 14C to radioactively decay is described by its half-life. C has a half-life of 5,730 years. In other words, after 5,730 years, only half of the original amount of 14C remains in a sample of organic material.

## Do all elements decay?

All elements with 84 or more protons are unstable; they eventually undergo decay. Other isotopes with fewer protons in their nucleus are also radioactive.

## What percent of carbon-14 would be left after 5730 years?

50 percent 5,730 years; The graph shows that 50 percent of the carbon-14 atoms have decayed after 5,730 years, so 5,730 is the half-life of carbon-14.