02_NuclearChemistry_PostLab_Spr24

Nuclear Chemistry Scarlet Roberts 3/18/2024 TOTAL: 30 points

Insert Last Name Estimating Half-Life Page 2 of 13 CHM 116 POST-LAB and LAB NOTEBOOK Nuclear Chemistry: Estimating Half Life of a “Radioactive” Element 1. Insert ONE picture of yourself in the appropriate lab attire and full PPE here ( include the Skittles® candy in your PPE picture ). **Remember to (1) show your full body so that we see you are wearing shoes; (2) wear your PPE (safety glasses, buttoned lab coat and gloves); (3) cover your lower legs and ankles (socks are required, even in Arizona); (4) tie back long hair in a ponytail or a bun; (5) remove jewelry. Note: Wearing full PPE may seem silly for tossing Skittles on a table, but we are establishing good lab protocol. If you have not received your lab kit (which contains your safety glasses), take the picture with what you have and include a note with your picture to explain why you are not wearing the complete PPE. I didn’t have q lab coat but used what I could. It was rather hard to find a affordable lab coat for my tests.

Insert Last Name Estimating Half-Life Page 3 of 13 2. Enter the data that you collected during the experiment (from Tables 1 and 2 in the procedure) HERE. Remember to adjust the number of Rounds for each Trial to how many you completed . Table 1 (Trial 1) Table 2 (Trial 2) Roun d Skittles “S” Up (Parent Atoms) Skittles “S” Down (Daughter Atoms) Cumulative Daughter Atoms Round Skittles “S” Up (Parent Atoms) Skittles “S” Down (Daughter Atoms) Cumulative Daughter Atoms 0 60 0 0 0 60 0 0 1 26 34 34 1 34 26 26 2 14 20 20 2 10 16 16 3 4 16 16 3 5 11 11 4 5 11 11 4 2 9 9 5 1 10 10 5 1 8 8 6 4 6 6 6 3 5 5 7 2 4 4 7 4 1 1 8 3 1 1 8 9 9 10 10 3. Describe , in 2 - 3 sentences , what happens mathematically to the total number of candies in each round (the general trend)? How is this related to the concept of half-life in nuclear reactions ( or, what is each round simulating with regards to half-life )? 4. Are your two data sets exactly the same? If not, explain (in 1 – 2 sentences) using your experimental data. With the first trial the half-life of the parent atom is independent. and in each round the number of parent atoms left will form the daughter atoms. The half- life of both trials is different but the same at the same time. For each trial it is up to how you throw the skittles that will depend on the amount of each test/ experiment that will ultimately decide the next generation. So, they will decrease over time. Until it is completely empty.

Insert Last Name Estimating Half-Life Page 4 of 13 5. Use a graphing software to create the x-y scatter plot showing the Number of parent nuclei remaining vs. Round # (do not connect your points). Your ONE graph will show data points from BOTH trials of the experiment . On your graph, the x-axis should be Round Number , and the y-axis should be Parent Atoms Remaining ( NOT the daughter atoms or cumulative daughter atoms ) in that Round. In general, scientific graphs show the independent variable on the x-axis and the dependent variable on the y-axis. Do NOT connect your points; no trend line needed and m ake sure to:  Label the axes including the units in parentheses.  Include a figure legend (text below the graph) explaining the data in your graph.  Remove any default title, legend, and gridlines.  You should use two different symbols to represent the two data sets (i.e. a square for Trial 1 and a circle for Trial 2) You will not receive credit if you draw your graph by hand. Excel or Google Sheets are good choices that you can learn how to use quickly if you don’t already have a favorite graphing program. See other general tips for making graphs in the How to Make a Graph in Excel document located in the Introductory Materials for this lab. 6. Consider the trend shown in your graph in Question 5. Is it linear, exponential growth or exponential decay ? Is this trend consistent with your expectations for the kinetics of a nuclear reaction? Briefly explain why in 2 – 3 sentences. 0 1 2 3 4 5 6 7 8 9 0 10 20 30 40 50 60 70 skittles trial 1 and 2 decay skittles 'S skittle 's daughter atoms round *** skittles 's skittles daughter atom*** rounds parent The trend of my graph shows an exponential decay. What is being shown is that the half-life of the parenting atom is decreasing as you do each test/ trial. Which would show a decrease within the graph.