The half-life of carbon-14 is 5,700 years.If 10 percent of the original carbon-14 is left in a structure, that structure would be _______ years old.

Question

Quizplus · Accepted Answer

The half-life of carbon-14 is 5,700 years, meaning the amount of carbon-14 halves every 5,700 years. If 10 percent is left, it means the carbon-14 has gone through more than three but less than four half-lives (since $1/2^3 = 12.5\%$ and $1/2^4 = 6.25\%$). Three half-lives equal 17,100 years and four half-lives equal 22,800 years, placing the age of the structure between 17,100 and 22,800 years.

The Half-Life of Carbon-14 Is 5,700 Years