Graphitic oxide and graphitic fluoride are nonconducting lamellar substances not obtained in true molecular forms that can be reproduced, but their formulas do approximate, respectively, the compositions of carbon dioxide and carbon monofluoride.carbon-13 (1.07 percent); 14 radioactive isotopes are known, of which the longest-lived is carbon-14, which has a half-life of 5,730 ± 40 years.

Carbon-14 is a radioactive isotope used to date organic material.

## Application of isotopes in carbon dating

Libby estimated that the steady-state radioactivity concentration of exchangeable carbon-14 would be about 14 disintegrations per minute (dpm) per gram.

In 1960, Libby was awarded the Nobel Prize in chemistry for this work.

The half-life of a radioactive isotope (usually denoted by $$t_$$) is a more familiar concept than $$k$$ for radioactivity, so although Equation $$\ref$$ is expressed in terms of $$k$$, it is more usual to quote the value of $$t_$$.

The currently accepted value for the half-life of will remain; a quarter will remain after 11,460 years; an eighth after 17,190 years; and so on.

Thus, using Equation $$\ref$$, $\ln \dfrac = (1.21 \times 10^) t \nonumber$ Thus, $t= \dfrac = 2 \times 10^3 \text \nonumber$ From the measurement performed in 1947 the Dead Sea Scrolls were determined to be 2000 years old giving them a date of 53 BC, and confirming their authenticity.

This discovery is in contrast to the carbon dating results for the Turin Shroud that was supposed to have wrapped Jesus’ body.

Carbon dating is most effective on material that predates the 1940s; this is due to above-ground nuclear tests increasing the amount of carbon-14 in the environment.

This inconsistent amount of carbon-14 renders the test less accurate but opens up testing possibilities not available for older samples.

Carbon dating has shown that the cloth was made between 12 AD.

Thus, the Turin Shroud was made over a thousand years after the death of Jesus.

Books, clothing and food remains are all archaeological artifacts that can be carbon dated.

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