Use this paragraph: The half-life of carbon-14 is 5,700 years. A certain sample of wood has 20 grams of carbon-14 when it is alive. How many grams of carbon will it have after 5,700 years?
A: 10 grams
B: 5 grams
C: 40 grams
D: 2 grams
The correct answer is B: 5 grams.
Since the half-life of carbon-14 is 5,700 years, after that time period, half of the original carbon-14 will have decayed. This means that the sample will have 10 grams of carbon-14 remaining.
To solve this question, we need to understand the concept of half-life. The half-life of carbon-14 is the amount of time it takes for half of a sample of carbon-14 to decay. In this case, the half-life of carbon-14 is given as 5,700 years.
Since the sample of wood has 20 grams of carbon-14 when it is alive, we can assume that after one half-life (5,700 years), half of the carbon-14 will decay. Therefore, after 5,700 years, the wood will have 10 grams of carbon-14 remaining.
Therefore, the answer to the question "How many grams of carbon will it have after 5,700 years?" is 10 grams (option A).
To find the number of grams of carbon the sample of wood will have after 5,700 years, we need to understand the concept of a half-life. The half-life of carbon-14 is 5,700 years, which means that over this period, half of the carbon-14 atoms will have decayed into nitrogen-14.
Since the sample starts with 20 grams of carbon-14, after one half-life (5,700 years), we will have half of that amount remaining, which is 10 grams.
Therefore, the correct answer is A: 10 grams.