Essay On 14c Dating

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Graded Assignment
Lab Report
Answer each question, using complete sentences. When you have finished, submit this assignment to your teacher by the due date for full credit.
(10 points)
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1. Use Table 1: Analysis of Decay in the laboratory guide to answer this question: Scientists find a piece of wood that is thought to be from an ancient fire circle. They find that the wood contains an amount of carbon-14 (14C) that is approximately 1/16 of the current atmospheric 14C levels. Determine approximately how many years ago the tree was chopped down to be used for the firewood. If you started with 1 million carbon-14 atoms, how many atoms would remain in the wood? 14C has a t1/2 of 5,750 years. Show your work!
Answer:
When you do the equation …show more content…

Why is 14C dating a good method to use for dating a human leg bone but not so good a method for dating a dinosaur bone? You may have to check the dates of the existence of humans and dinosaurs on earth on a chart showing the geological eras.
Answer:
Carbon-14 is good for human leg bones because of the date we exist. But dinosaurs because carbon-14 is limited to about 50,000 years and now little carbon-14 is left and the dating on a dinosaur would be very inaccurate.

(5 points)
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3. Potassium-40 (40K) is a radioactive material that decays into argon-40 (40Ar). The half-life of a sample of 40K is 1.3 billion years. Rocks containing 40K have been around since the formation of the earth, and 40Ar gas has been accumulating in those rocks since the earth formed. However, when rocks are heated by volcanic action, all the 40Ar leaves the rock when the gases escape. Create a scenario and discuss, based on your knowledge of half-life, the value of potassium-argon dating to geologists.
Answer:
If you know the half-life of k-40 than you can use the ratio of Ar-40: Kr-40 in a rock sample of a volcano you can find out the time the volcano erupted. If y0uu know this than it can help scientist learn more about the earths tectonic

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