The half-life of ¹⁴C, a radioactive element of carbon, is approximately 5,000 years. The ratio of ¹⁴C to ¹²C in a fossil 25,000 years old would be _______ that of a living organism today.

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Since the half-life of ¹⁴C is approximately 5,000 years, after 5,000 years, half of the original amount of carbon in a fossil or living organism would remain. After another 5,000 years (10,000 years total), a quarter of the original amount would remain. After 15,000 years, an eighth of the original amount, and so on. Therefore, if a fossil is 25,000 years old, we can calculate how many half-lives have passed: 25,000 years / 5,000 years = 5 half-lives So, the ratio of ¹⁴C to ¹²C in a fossil 25,000 years old would be: (1/2)^5 : 1 = 1/32 : 1 Therefore, the ratio in the fossil would be 1/32 of that in a living organism today. The answer is D) 1/32.

The Half-Life of 14C, a Radioactive Element of Carbon, Is

The Half-Life of ¹⁴C, a Radioactive Element of Carbon, Is