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Radioactive Simulation544957085090Website: Click Half Life tab on top. Add a Carbon-14 atom to the play area. What happens to that Carbon-14 atom? ________________________________________________________________________Do all Carbon-14’s decay at the same time? ____________________________________________and Using 20 Carbon-14s, draw the pie chart at the following time periods:5000 Years10000 years15000 yearsRedo the above with 100 Carbon-14 atoms and fill in the three boxes below.5000 Years10000 years15000 yearsHow do the pie charts of 20 atoms compare to those of 100 atoms? _______________________________________________________________________________________________________________________________________________________________________________________Decay RateClick Decay Rates tab on top. Use the slider and move it all the way to the right. Watch the graph at the bottom of the screen. Use the pause button if needed.Sketch the decay curves ( % remaining vs time) for Carbon-14 and Uranium-238:3213735122555Uranium-23800Uranium-23826670122555Carbon-1400Carbon-14 Now, answer the following questions:After one half-life (4.5 billion years), what percent of the original uranium remains?After two half-lives (9 billion years), what percent of the original uranium remains?After three half-lives (13.5 billion years), what percent of the original uranium remains?Suppose you found a rock, and through testing found out that it had just as much lead-206 as uranium-238. How old would you conclude this rock to be?If you run the decay rate simulation several times, you will notice that the lines do not always cross at the same spot. This is due to the small number of atoms used in the simulation. Where do you think the lines would cross if we had used millions or even billions of atoms instead?_______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________MeasurementClick the Measurement tab at the top of the screen.Click “Plant Tree” at the bottom of the screen. The tree will grow and live for about 1200 years, then die and begin to decay. Let the time run and watch the graph at the top of the screen.According to the graph, what is the percent of C-14 in the tree while it is alive? ____ Why?________________________________________________________________Use the graph to approximate the age of the dead tree, depending on the % of C14 left. Hint: you can use the pause button to stop the count.% of C1487634210Age of tree(in years)Now do the same for the rock. Erupt the volcano and estimate the age of the igneous rock sample% of U23887634210Age of tree(in years)Dating GameClick the “Dating Game” tab at the top of the screen.You can drag the probe to different items on or below the surface of the earth. The probe tells you how much of the original element is still in the rock or fossil. You can measure C-14 or U-238, whichever works better for the item you are measuring.You can use the graph to match the percent of element remaining, and then use the time shown to estimate the age of the rock or fossil.ItemAgeElement UsedAnimal SkullHouseLiving TreeDistant Living TreeDead TreeBoneWooden CupHuman SkullFish BonesRock 1Rock 2Rock 3129962580242Hint: For the last four items on the list, neither C14 or U238 will work well. Select “Custom”, and pick a half-life that gives you something other than 0.0% on the probe.00Hint: For the last four items on the list, neither C14 or U238 will work well. Select “Custom”, and pick a half-life that gives you something other than 0.0% on the probe.Rock 4Rock 5Fish FossilDinosaur SkullTrilobiteSmall Human SkullComprehension Question:You happen upon an antiques store and the clerk claims that he has a belt that was once worn by Alexander the Great, around 350 BC. You radiocarbon date it and find the percent of carbon to be 75% remaining. Could the belt be genuine? Explain your reasoning below._______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ ................
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