ime (year) Remaining Radioactive Atoms 100 1000 85 2000 72 Radioactive Decay 3000 61 4000 52 5000 44 6000 38 100 7000 32 8000 27 9000 23 10000 20 11000 17 12000 14 13000 12 14000 10 15000 9 16000 17000 18000 19000 10,000 20,000 200005:010 ...eet02-xythos.content.blackboardcdn.com 3,000 61 4,000 52 5,000 44 6,000 38 7.000 32 8,000 27 9.000 23 10,000 20 1 1,000 17 12,000 14 13,000 12 14,000 10 15,000 9 16,000 17,000 6 18,000 5 19,000 5 20,000 2 Element A Graph: Radioactive Decay 100 90 80 70 60 To find the half-life, find half of the amount of radioactive material that you Remaining Radioactive Atoms started with. In this case, it is 50 (100 / 2 = 50). The half-life is equivalent to the 8 amount of time required to reach that 30 amount. In this example the half-life is about 4,200 years. 20 10 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Time (Years) Element B Graph: Copy and Paste Excel Graph for Element B here Element C Graph:5:00 0 ...eet02-xythos.content.blackboardcdn.com [1] PHSC 111 - Introduction to Physical Science Virtual Radioactive Decay Lab This virtual lab runs on Flash. If your computer still runs Flash you may access the simulation at: http:/glencoe.mheducation.com/sites/dl/free/0078693896/280405/E18.html If the Flash simulation does not run on your computer you may access a screencast of the simulation at: https://www.youtube.com/watch?v=wk8AiOhv6Lo&feature-youtu.be (Note that there is no sound to this screencast.) Read through the directions on the left side of the screen (screenshot below). Pause the screencast as needed. ELEMENT A Video The some of decay of a sad Screenshot of Virtual Radioactivity Record your data for Elements A, B, C and D in the table on the next page. Then, using the generic Excel file on Blackboard, graph the data for EACH element. Copy and paste the Excel graph for each element into this document. Element A has been done for you as an example. (Note: The Excel file available on Blackboard shows the data and graph for Element A. Save this file under a different name and then replace the data for Element A with the data for another element. Copy and paste the Excel graph in the appropriate location below. Do the same for each of the other Element data.) Finally, respond to the questions. Time Element A Element B Element C Element D (years) 100 100 100 100 1,000 85 2,000 72 3,000 61 4,000 52 5,000 44 6,000 38 + 4 . . .5:010 A ...eet02-xythos.content.blackboardcdn.com 10 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 Time (Years) Element B Graph: Copy and Paste Excel Graph for Element B here Element C Graph: Copy and Paste Excel Graph for Element C here w Element D Graph: Copy and Paste Excel Graph for Element D here Questions: 1. According to your data, what is the approximate half-lives of each of the hypothetical elements? a. Element A: 4,200 years b. Element B: Element C: d. Element D: 2. Look at the general shape of the graphs for each element. What do all (or at least most) have in common? 3. The shorter an element's half-life, the more radioactive the element is. Which of the four elements is the most radioactive? 4. What happens to a radioactive isotope as it decays? Does the radioactive material disappear? Explain. 5. After 3 half-lives, one-eighth of the original radioactive isotope still remains. If a sample started with one billion radioactive isotopes (at time = 0), how many radioactive isotopes would remain after 3 half-lives? Explain your reasoning