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Crime Scene Lab. Can you solve the mystery?. A crime has been committed!. The police investigated the scene and found a mysterious white powder on the ground and victim. They were able to find nearby several Suspects that also had a similar white powder on them. This morning a jogger
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Crime Scene Lab Can you solve the mystery?
A crime has been committed! The police investigated the scene and found a mysterious white powder on the ground and victim. They were able to find nearby several Suspects that also had a similar white powder on them This morning a jogger discovered a murder victim!
It is up to you! • As a crime lab technician, it is your job to test and analyze the results to determine if you can use the mystery white powder to match a suspect to the crime scene.
How do you do this? • You compare the results of tests. • Some tests will result in a chemical reaction! • Others will only involve a physical change or mixing of substances. • First you will test some known substances to see what their properties are. • Then you will compare these results to the results of the crime scene and suspect samples. • If the results are identical between a known sample, the crime scene & a suspect you can conclude that they are the same thing. • If this is the case, then you can say that a suspect has been matched to the crime scene and is probably guilty! • If you cannot match results, then that suspect is probably not connected to the crime scene and is probably innocent! • But you may have to interpret imperfect results! So be prepared to make an inference…
Known Substance tests: Each known substance is a white powder that appears to be identical to the Samples collected from the crime scene and the suspects. Vinegar Iodine Water Vinegar Iodine Water For each test, describe the reaction you observe with one or more of the following descriptions: “No Change” “Dissolved” Look for the white color to disappear “Fizzed” “Turned (name the color)” Baking Soda Samples Corn Starch Samples
Known Substance tests: Each known substance is a white powder that appears to be identical to the Samples collected from the crime scene and the suspects. Water Vinegar Iodine Water Vinegar Iodine For each test, describe the reaction you observe with one or more of the following descriptions: “No Change” “Dissolved” “Fizzed” “Turned (name the color)” Powdered Sugar Samples Baking Powder Samples
Mystery Substance tests: Water Vinegar Iodine Water Vinegar Iodine Water Vinegar Iodine Each of these samples were collected from the indicated location. The white powders appear to be identical to each other. See if you can match reactions to the known substances and then match a suspect to the crime scene. Suspect A Samples Suspect B Samples Crime Scene Samples