Team Name: ______

Fayettville-Manlius Science Olympiad Invitational

Saturday, December 17, 2016

FORENSICS

ANSWER KEY

DO NOT OPEN THIS PACKET UNTIL YOU ARE INSTRUCTED TO DO SO

  • All answers must go in this packet.
  • Be sure to put your team name, team code, number, and your names below.
  • You may take this packet apart, but it is your responsibility to put it back together in order at the end of the test. Failure to do so will result is a deduction of 5 points!
  • A 10% penalty may be given if the area is not cleaned up as designated by the event supervisor.

ANSWER PACKET

Team Name: / Team Number:
Participant Names:

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Team Name: ______

Part 1: Quantitative Analysis (20 points)

Identify powders #1-8 here. Give the chemical name or formula.

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Team Name: ______

Powder / Identification
chemical name OR symbol
(2 pts each) / Who does this implicate?
(if anyone)
(1 pt each)
#1 / NaCl
sodium chloride / no one
#2 / NH4Cl
ammonium chloride / no one
#3 / CaCO3
calcium carbonate / Joseph Johnson
#4 / C6H12O6
glucose / Scott Skelton
#5 / cornstarch / Scott Skelton

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Team Name: ______

Write the balanced chemical equation representing the positive NaOH test for magnesium sulfate. (2 pts)

MgSO4(aq) + 2NaOH(aq)  Na2SO4(aq) + Mg(OH)2(s)

Write the balanced chemical equation representing the positive HCl test for sodium bicarbonate. (2 pts)

NaHCO3(s) + HCl(aq)  CO2(g) + H2O(l) + NaCl(aq)

Write the chemical formula for the gas that is liberated when ammonium chloride reacts with sodium hydroxide. (1 pt.)

NH4Cl(aq) + NaOH(aq)  NH3(g) + NaCl(aq) + H2O(l)

Part 2: Polymers (21 points)

Identify samples #6-#8below.

#6 – used to make water bottles, 2-liter soda bottles, cooking oil bottles

#7 – used in drinking cups – positive acetone test

#8 – used in construction, commonly pipes – positive copper wire test

Plastic / Identification
full name OR abbreviation
(2 pts each) / Who does this implicate?
(if anyone)
(1 pt each)
#6 / PETE / Joseph Johnson
#7 / PS / no one
#8 / PVC / no one

Identify hair samples #9 and #10 here.

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Team Name: ______

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Team Name: ______

Hair Sample / Identification
(2 pts each) / Who does this implicate?
(if anyone)
(1 pt each)
#9
/ dog / Joseph Johnson
#10
/ horse / no one

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Team Name: ______

Identify fiber samples #11 and #12 here. You are permitted to do burn tests on theses and/or view them under the microscope.

#11 –smells like burning hair when burned

#12 –smells like burnt paper or leaves when burned

Fiber / Identification
(2 pts each) / Who does this implicate?
(if anyone)
(1 pt each)
#11 / wool / Joseph Johnson
#12 / cotton / Scott Skelton

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Team Name: ______

Part 3: Chromatography/Spectroscopy (15 points)

  1. Paper Chromatography (9 points)

Consider the following chromatogram. Calculate Rf values for each of the pigments. Show all of your work below and circle your answer(s).

Blue (3 points)
3.60 cm = 0.818
4.40 cm / Purple (3 points)
2.65 cm = 0.602
4.40 cm
Yellow (3 points)
0.90 cm = 0.21
4.40 cm
  1. Mass Spectroscopy – 6 points

Data retrieved from Spectral Database for Organic Compounds SDBS

The oily material found at the crime was analyzed using mass spectrometry and can be found on the crime scene evidence sheet. Using the structures below, identify which structure matches the mass spectrum. Please circle your answer. (4 points)

Joan Smith /
Joseph Johnson /

Scott Skelton /

Suspect(s) that matched the oily substance found at the crime scene (if any): __Joseph Johnson___ (2 pts)

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Team Name: ______

Part 4: Crime Scene Physical Evidence (15 points)

  1. Fingerprints (5 points)

Below are fingerprints from both suspects. Analyze them and determine which suspect(s), if any, matches the fingerprint found at the crime scene. Consult the crime scene evidence paper for the print.

Joseph Johnson

Scott Skelton

Suspect(s) that matched the fingerprint found at the crime scene (if any): ___Scott Skelton___ (2 points)

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Team Name: ______

Look at the fingerprint below and answer the following questions.

What type of ridge pattern is it? __whorl__ (1/2 point)

Circle the delta(s) on the picture. (1/2 point)circled in red

Identify the minutiae patterns that are circled. (1/2 point each)

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Team Name: ______

  1. Blood Type (10 points)

Blood was found at the crime scene that was determined to be type AB-. Blood has been collected from both suspects and the victim, which need to be typed. Please write the blood type in the box provided.

Anti-A Serum / Anti-B Serum / Anti-Rh Serum / Blood Type
(2 pts each)
Joan Smith / / / / B-
Joseph Johnson / / / / O+
Scott Skelton / / / / AB-

Suspect(s) that matches the crime scene (if any): ___Scott Skelton____(2 pts)

Look at the following blood smears on microscope slide. Please identify the source of the blood sample. (2 pts)

___avian blood____

Part 5: Analysis of the Crime (30 points)

For each of the suspects circle either “Hold for Questioning” or “Release”. In the space provided for each suspect, summarize ALL of the evidence that led you to your decision.

______

Joseph JohnsonHold for QuestioningRelease

mass spec matched crime scene

CaCO3 matched crime scene

PETE matched crime scene

dog hair matched crime scene

wool matched crime scene

______

Scott SkeltonHold for QuestioningRelease

fingerprint matched crime scene

blood matched crime scene

glucose matched crime scene

cornstarch matched crime scene

cotton matched crime scene.

______

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