The currently accepted value for the half-life of 14C is 5,730 years. This means that after 5,730 years, only half of the initial 14C will remain; a quarter will remain after 11,460 years; an eighth after 17,190 years; and so on.

How much carbon-14 would remain in a fossil after 11400 years?

That is, 16 g of 14C would remain after 5700 years and 8 g would remain after 11,400 years.

How long does it take for carbon-14 to decay completely?

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. After an additional 5,730 years–or 11,460 years total–only a quarter of the 14C remains.

What percentage of the original amount of carbon-14 will remain after 20000 years carbon-14 has a half-life of 5700 years?

50% Explanation: Well, if the half-life of 14C is 5700 years, then that means after 5700 years have happened, there will be half of the original amount, i.e. 50% of the original amount of 14C left.