Science Olympiad Belleville Invitational Forensics : The Missing School Bus Saturday, November 11, 2017

Transcription

1 The Scenario: Science Olympiad Belleville Invitational Forensics : The Missing School Bus Saturday, November 11, 2017 This morning police received a phone call from Johnson High School reporting that the activity school bus was missing. The bus was purchased last year to allow field trips during the day for classes as well as athletic and other extracurricular activities in the evenings. The police arrived promptly and started to work, and they were able to collect fingerprints from the area where the bus was parked (behind the bus garage where all of the regular school buses are parked) and a note that said No more bus for you! was found. A paper chromatogram was made of the ink. This chromatogram was developed in rubbing alcohol for 10 minutes. Eight powders (Samples A H), four polymers (Samples I-L), two fibers (Samples M & N), and two hairs (samples O & P) were also collected at the scene. The bus garage is located across the street from the main office of the school. In addition, a DNA sample was taken from a drop of blood at the bus garage. In addition, a whorl fingerprint was found at the scene. Six potential suspects have been identified: Bus Driver Harry: Harry was getting close to retirement and was not happy that he was selected to drive the activity bus in the evenings as he wanted to get home to rest after a long day. President Jon: Jon is the President of the School Board and was recently trying to overcome a significant district budget shortfall. He had proposed the elimination of all field trips and extracurricular travel and selling the activity bus to help fix the deficit. Coach Bob: Bob was not happy that he had to share the bus with teachers for field trips and other extracurricular activities. He wanted the bus to himself and his team and he had recently threatened Principal Allan that if he couldn t use the bus, nobody could use the bus. Principal Allan: Allan was also concerned about the budget shortfall and was trying to keep peace between Coach Bob and Teacher Jane, who also wanted primary use of the activity bus. Teacher Jane: Jane was upset with Coach Bob as she wanted to take the kids on more field trips but the bus wasn t always available when she needed it. She had a general dislike for coaches after a bad experience in the past. Lazy Joey: Joey was a student who did not want to participate in activities after school, but his parents required him to be active. He had been recorded telling students in the days leading up to the disappearance that he wished the bus would just disappear. The samples have been provided to you. Police fingerprinted and interviewed each of the suspects. Your task, detectives, is to analyze the substances found at the crime scene, complete a chromatogram on the black marker, and determine which if any of the samples found at the scene belong to which of the suspects and determine who is most likely to have taken the bus. You have 50 minutes. Good luck.

2 Name: Bus Driver Harry Age: 64 Pants: Wool Pet: None Eyes: Brown Pen: D Additional info: Likes to eat salt and vinegar potato chips. Likes to collect plastic pop bottles and was changing the license plates on his car yesterday. SUSPECT INTERVIEW SHEET Fingerprint DNA Name: President John Age: 59 Pants: Cotton Pet: Cow Eyes: Hazel Pen: D Additional info: Is a diabetic and uses glucose often. Was working yesterday to replace the PVC pipes in his basement and used a hack saw to cut the pipes, leaving bits of plastic behind. Name: Coach Bob Age: 48 Pants: Silk Pet: Squirrel Eyes: Green Pen: C Additional info: Has been very busy cleaning and disinfecting the weight room for the past couple of days. He has also been putting up new sheetrock walls in the weight room at school. Name: Principal Allan Age: 52 Pants: Polyester Pet: Horse Eyes: Blue Pen: B Additional Info: Likes to volunteer in the garden center down the block from home by spreading fertilizer. Busy making meals in plastic trays for the homeless lately. Name: Teacher Jane Age: 35 Pants: Nylon Pet: Bat Eyes: Brown Pen: B Additional Info: Has heartburn often and is currently working on an acid/base titration project for Chemistry. She was helping Principal Allan with a fireworks demonstration for town recently. She has a plastic bottle collection. Name: Lazy Joey Age: 16 Pants: Spandex Pet: Horse Eyes: Green Pen: A Additional Info: Likes to bake often. Spent the previous day making pickles and Jello Molds and likes to eat vinegar potato chips. Always eats on plastic plates and is diabetic. Has a trading card collection.

3 Part A: Qualitative Analysis (20%) You have eight samples (labeled A-H) to identify. Provided materials include: Iodine reagent, 2 M HCl, 2M NaOH, waste beaker, and a wash bottle with distilled water. Place all wastes into the waste beakers provided. There are also several questions to answer regarding the substances and their properties. NOTE: When answering the questions, be sure to consider all the possible substances, not just those identified. Part B: Polymers and Fibers (15%) You have four polymers (I, J, K, L) to identify. You don't actually have samples, just the information below. Substance/Solution Density (g/ml) Corn Oil % Isopropyl Alcohol Distilled Water % NaCl % NaCl 1.19 Saturated NaCl 1.25 Additionally: Sample I is nearly at buoyant equilibrium in 25% NaCl solution Sample J burns with a green flame Sample K is nearly at buoyant equilibrium in distilled water Sample L is nearly at buoyant equilibrium in 46% Isopropyl Alcohol Fiber M under an Electron microscope Fiber N under the Electron Microscope Hair O Photomicrograph Hair P Photomicrograph

4 Part C: Chromatography/Spectroscopy (15%) Pen A Pen B Pen C Pen D Part D: Crime Scene Physical Evidence (15%) DNA Found at the Scene Part E: Analysis of the Crime (30%) Write an analysis of the crime that explains which pieces of evidence implicate the suspect you selected. Also provide reasons why the other suspects were not chosen. You must limit your analysis to the one side of the answer sheet only be concise!

5 WI Belleville Invitational 2017 Saturday, Nov 11, 2017 Forensics Event Answer Sheet Team Name: Team Number: Names of Participants: Part A: Qualitative Analysis (20%) 40 Total Points Point value Answer Question 1. 3 Identity of Sample A 2. 1 On what basis did you make the ID? 3. 1 Which suspect(s), if any, does this piece of evidence implicate? 4. 3 Identity of Sample B 5. 1 On what basis did you make the ID? 6. 1 Which suspect(s), if any, does this piece of evidence implicate? 7. 3 Identity of Sample C 8. 1 On what basis did you make the ID? 9. 1 Which suspect(s), if any, does this piece of evidence implicate? Identity of Sample D On what basis did you make the ID? Which suspect(s), if any, does this piece of evidence implicate? Identity of Sample E On what basis did you make the ID? Identity of Sample F On what basis did you make the ID? Identity of Sample G

6 20. 1 On what basis did you make the ID? Identity of Sample H On what basis did you make the ID? Part B: Polymers and Fibers (20%) 40 Total Points Point value Answer Question Identity of Polymer I What type of polymerization is used to make this polymer? Identity of Polymer J What type of polymerization is used to make this polymer? Identity of Polymer K What type of polymerization is used to make this polymer? Identity of Polymer L What type of polymerization is used to make this polymer? Identity of Fiber M Identity of Fiber N 40. 1

7 41. 3 Identity of Hair O Identity of Hair P Which polymer is used in trading card holders? What polymer is used in car headlights? Which polymer is used in license plate holders? Which polymer is used in bottle caps? Part C: Chromatography/Spectroscopy (15%) 30 Total Points Attach your completed chromatograph above Which suspect(s) does this evidence implicate? Determine the R f values for the three components in the following chromatogram: (4 pts each) R f (51) (52) (53) Calculate the Rf above for (51) Calculate the Rf above for (52) Calculate the Rf above for (53) What does Rf stand for?

8 Part D: Crime Scene Physical Evidence (15%) 30 Total Points Point value Answer Question Which suspect's DNA was found at the scene? Which suspects have arches in their fingerprints? Which suspects have loops in their fingerprints? Which suspects have whorls in their fingerprints? Which suspect(s) are implicated by the fingerprint evidence? What does AFIS stand for? What approximate percentage of the population has arch fingerprints? What approximate percentage of the population has loop fingerprints? What approximate percentage of the population has whorl fingerprints? How many ridges does the average fingerprint have? Prints on a porous surface such as paper could be obtained using which type of process? What are the three main ways to lift fingerprints? What is the name given to the 10 to 16 points of a fingerprint used to compare to a database?

9 Part E: Analysis of the Crime Scene (30%) 60 Total Points Write an analysis of the crime that explains which pieces of evidence implicate the suspect you selected. Also provide reasons why the other suspects were not chosen. You must limit your analysis to this side of the answer sheet only be concise! Start by filling out the table below. Mark a check mark if the evidence implicates the suspect. Don't forget to write the analysis after the table! Suspect A B C D E F G H I J K L M N O P CH DNA FP Bus Driver Harry President John Coach Bob Principal Allan Teacher Jane Lazy Joey

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11 The Scenario: Science Olympiad Belleville Invitational Forensics : The Missing School Bus Saturday, November 11, 2017 This morning police received a phone call from rural Johnson High School reporting that the activity school bus was missing. The bus was purchased last year to allow field trips during the day for classes as well as athletic and other extracurricular activities in the evenings. The police arrived promptly and started to work, and they were able to collect fingerprints from the area where the bus was parked (behind the bus garage where all of the regular school buses are parked) and a note that said No more bus for you! was found. A paper chromatogram was made of the ink. This chromatogram was developed in rubbing alcohol for 10 minutes. Eight powders (Samples A H), four polymers (Samples I-L), two fibers (Samples M & N), and two hairs (samples O & P) were also collected at the scene. The bus garage is located across the street from the main office of the school. In addition, a DNA sample was taken from a drop of blood at the bus garage. In addition, a whorl fingerprint was found at the scene. Six potential suspects have been identified: Bus Driver Harry: Harry was getting close to retirement and was not happy that he was selected to drive the activity bus in the evenings as he wanted to get home to rest after a long day. President Jon: Jon is the President of the School Board and was recently trying to overcome a significant district budget shortfall. He had proposed the elimination of all field trips and extracurricular travel and selling the activity bus to help fix the deficit. Coach Bob: Bob was not happy that he had to share the bus with teachers for field trips and other extracurricular activities. He wanted the bus to himself and his team and he had recently threatened Principal Allan that if he couldn t use the bus, nobody could use the bus. Principal Allan: Allan was also concerned about the budget shortfall and was trying to keep peace between Coach Bob and Teacher Jane, who also wanted primary use of the activity bus. Teacher Jane: Jane was upset with Coach Bob as she wanted to take the kids on more field trips but the bus wasn t always available when she needed it. She had a general dislike for coaches after a bad experience in the past. Lazy Joey: Joey was a student who did not want to participate in activities after school, but his parents required him to be active. He had been recorded telling students in the days leading up to the disappearance that he wished the bus would just disappear. The samples have been provided to you. Police fingerprinted and interviewed each of the suspects. Your task, detectives, is to analyze the substances found at the crime scene, complete a chromatogram on the black marker, and determine which if any of the samples found at the scene belong to which of the suspects and determine who is most likely to have taken the bus. You have 50 minutes. Good luck.

12 Name: Bus Driver Harry Age: 64 Pants: Wool Pet: None Eyes: Brown Pen: D Additional info: Likes to eat salt and vinegar potato chips. Likes to collect plastic pop bottles and was changing the license plates on his car yesterday. SUSPECT INTERVIEW SHEET Fingerprint DNA Name: President John Age: 59 Pants: Cotton Pet: Cow Eyes: Hazel Pen: D Additional info: Is a diabetic and uses glucose often. Was working yesterday to replace the PVC pipes in his basement and used a hack saw to cut the pipes, leaving bits of plastic behind. Name: Coach Bob Age: 48 Pants: Silk Pet: Squirrel Eyes: Green Pen: C Additional info: Has been very busy cleaning and disinfecting the weight room for the past couple of days. He has also been putting up new sheetrock walls in the weight room at school. Name: Principal Allan Age: 52 Pants: Polyester Pet: Horse Eyes: Blue Pen: B Additional Info: Likes to volunteer in the garden center down the block from home by spreading fertilizer. Busy making meals in plastic trays for the homeless lately. Name: Teacher Jane Age: 35 Pants: Nylon Pet: Bat Eyes: Brown Pen: B Additional Info: Has heartburn often and is currently working on an acid/base titration project for Chemistry. She was helping Principal Allan with a fireworks demonstration for town recently. She has a plastic bottle collection. Name: Lazy Joey Age: 16 Pants: Spandex Pet: Horse Eyes: Green Pen: A Additional Info: Likes to bake often. Spent the previous day making pickles and Jello Molds and likes to eat vinegar potato chips. Always eats on plastic plates and is diabetic. Has a trading card collection.

13 Part A: Qualitative Analysis (20%) You have eight samples (labeled A-H) to identify. Provided materials include: Iodine reagent, 2 M HCl, 2M NaOH, waste beaker, and a wash bottle with distilled water. Place all wastes into the waste beakers provided. There are also several questions to answer regarding the substances and their properties. NOTE: When answering the questions, be sure to consider all the possible substances, not just those identified. Part B: Polymers and Fibers (15%) You have four polymers (I, J, K, L) to identify. You don't actually have samples, just the information below. Substance/Solution Density (g/ml) Corn Oil % Isopropyl Alcohol Distilled Water % NaCl % NaCl 1.19 Saturated NaCl 1.25 Additionally: Sample I is nearly at buoyant equilibrium in 25% NaCl solution Sample J burns with a green flame Sample K is nearly at buoyant equilibrium in distilled water Sample L is nearly at buoyant equilibrium in 46% Isopropyl Alcohol Fiber M under an Electron microscope Fiber N under the Electron Microscope Hair O Photomicrograph Hair P Photomicrograph

14 Part C: Chromatography/Spectroscopy (15%) Pen A Pen B Pen C Pen D Part D: Crime Scene Physical Evidence (15%) DNA Found at the Scene Part E: Analysis of the Crime (30%) Write an analysis of the crime that explains which pieces of evidence implicate the suspect you selected. Also provide reasons why the other suspects were not chosen. You must limit your analysis to the one side of the answer sheet only be concise!

15 WI Belleville Invitational 2017 Saturday, Nov 11, 2017 Forensics Event Answer Sheet Team Name: KEY Team Number: Names of Participants: Part A: Qualitative Analysis (20%) 40 Total Points Point value 1. 3 Answer Sodium Acetate Identity of Sample A Question Odor Bus Driver Harry, Lazy Joey Glucose Positive Benedict's Test Lazy Joey, President John Boric Acid Flame Test None Potassium Chloride Flame Test None Lithium Chloride Flame Test None Sodium Chloride Conductivity Lazy Joey Cornstarch On what basis did you make the ID? Which suspect(s), if any, does this piece of evidence implicate? Identity of Sample B On what basis did you make the ID? Which suspect(s), if any, does this piece of evidence implicate? Identity of Sample C On what basis did you make the ID? Which suspect(s), if any, does this piece of evidence implicate? Identity of Sample D On what basis did you make the ID? Which suspect(s), if any, does this piece of evidence implicate? Identity of Sample E On what basis did you make the ID? Identity of Sample F On what basis did you make the ID? Identity of Sample G

16 Color, Texture, Lack of other results Lazy Joey Ammonium Chloride Rxn with Base to produce ammonia Principal Allan On what basis did you make the ID? Identity of Sample H On what basis did you make the ID? Part B: Polymers and Fibers (20%) 40 Total Points Point value Answer PMMA Identity of Polymer I Question Addition None PVC Addition President John Non-Expanded PS Addition Lazy Joey, Principal Allan, Bus Driv Harry HDPE Addition Bus Driver Harry, Teacher Jane Spandex Lazy Joey Wool Bus Driver Harry What type of polymerization is used to make this polymer? Identity of Polymer J What type of polymerization is used to make this polymer? Identity of Polymer K What type of polymerization is used to make this polymer? Identity of Polymer L What type of polymerization is used to make this polymer? Identity of Fiber M Identity of Fiber N

17 Horse Principal Allan, Lazy Joey Cow President John PP PMMA Non-Expanded PS HDPE Identity of Hair O Identity of Hair P Which polymer is used in trading card holders? What polymer is used in car headlights? Which polymer is used in license plate holders? Which polymer is used in bottle caps? Part C: Chromatography/Spectroscopy (15%) 30 Total Points Attached Above Lazy Joey Attach your completed chromatograph above. Which suspect(s) does this evidence implicate? Determine the R f values for the three components in the following chromatogram: (4 pts each) R f (51) (52) (53) / / / Retention Factor OR Rate of Flow Calculate the Rf above for (51). Calculate the Rf above for (52). Calculate the Rf above for (53). What does Rf stand for?

18 Part D: Crime Scene Physical Evidence (15%) 30 Total Points Point value Answer Lazy Joey Coach Bob Question Which suspect's DNA was found at the scene? Which suspects have arches in their fingerprints? Teacher Jane, Principal Allan Lazy Joey, Bus Driver Harry, Presid Jon Which suspects have loops in their fingerprints? Which suspects have whorls in their fingerprints? Lazy Joey, Bus Driver Harry, Presid Jon Which suspect(s) are implicated by the fingerprint evidence? Automated Fingerprint Identification System What does AFIS stand for? 5% What approximate percentage of the population has arch fingerprints? 70% What approximate percentage of the population has loop fingerprints? 25% What approximate percentage of the population has whorl fingerprints? Around 150 How many ridges does the average fingerprint have? Iodine Fuming OR Ninhydrin Ninhydrin Solution, Physical Developer, CA Soln, Dusting Minutiae Prints on a porous surface such as paper could be obtained using which type of process? What are the three main ways to lift fingerprints? What is the name given to the 10 to 16 points of a fingerprint used to compare to a database?

19 Part E: Analysis of the Crime Scene (30%) 60 Total Points Write an analysis of the crime that explains which pieces of evidence implicate the suspect you selected. Also provide reasons why the other suspects were not chosen. You must limit your analysis to this side of the answer sheet only be concise! Start by filling out the table below. Mark a check mark if the evidence implicates the suspect. Don't forget to write the analysis after the table! Suspect A B C D E F G H I J K L M N O P CH DNA FP Bus Driver Harry President John Coach Bob Principal Allan Teacher Jane X X X X X X X X X X X X Lazy Joey X X X X X X X X X X Lazy Joey has, by far, the most evidence against him. Coach Bob has no evidence against him, so he couldn't have done it without leaving at least one piece of evidence. The fact that the physical evidence directly implicates Lazy Joey is hard to discount (chromatography, fingerprint, & DNA evidence). Since there isn't more information about the fingerprint, hard to put too much stock on that evidence. Glucose is common for diabetics so not surprising sample B was found at the scene. PVC is a very common plastic so it shouldn't implicate President John either. It appears that this location may be rural (no mention of public transit, bus garage located near school, only one bus for all field trips for the district), so cow hair would be more likely, put less emphasis on it. Since Ammonium Chloride is in fertilizer, it could be used by many people, so put less emphasis on that evidence. HDPE is also a common plastic so less emphasis on that either. The evidence clearly points to Lazy Joey. X