Summary of Thoughts:Prep:

Clothing and safety requirements (goggles, lab coat/apron, pants, closed shoes)Bring the stuff you can bring especially notes

Part A: Unknown Solids, Liquids and MetalsMake flow charts (which tests tell you which cmpds you have)Study the possible combinations

Part B: “Polymer” testingKnow the hairs (both the appearance of the medulla inside and the scale pattern on the surface)Know the fibers (microscope image identification)Know the polymer density ranges and burn test results

Part C: Paper Chromatography/Mass SpectrometrySee the WSU SO website for my paper chromatography primerWe will do Mass Spec on a drug sample this year (give mass spec, and 4 possible structures)

Part D: Physical EvidenceFingerprints are a givenPossible DNA chromatograms this yearBlood spatters and shoe prints are a possibility as wellGlass is a favorite of mine

Part E: Crime Scene AnalysisLeave time to write your essayWho and Why…..Who and Why NotStart to think: I KNOW that evidence X can be associated with person YNeatness, grammar, spellingClarity of thought (can I easily follow what you are doing)Correctness of associations (are you properly associating evidence X with person Y)Correctness of conclusions (are you properly interpreting your evidence and associations)

Science Crime Busters (SCB) &Forensics (FOR) 2011

Physical Science & Chemistry

Both of these events are 5 part events:1. Qualitative analysis of unknown materials

2. Polymer Testing

3. Chromatography

4. Crime Scene Evidence

5. Analysis

ChangesNote sheet clarified

Safety clothing requirements

Change in part b—water quality testing

Removal of hairs and fibers from part d

Tie breaker rule

Part 0: Being PreparedEquipment:• Bring your kit. Bring everything allowed in your kit.

Safety:• Lab coat, apron or other type of front torso, leg and arm

protection• Eyewear: Science Olympiad is very clear that the team

must wear Chemical/Splash resistant eyewear. Seal around the face, do not have direct vents. http://soinc.org/eye_protection

Clothing:• Closed toe shoes• “Pants”: long skirts acceptable but not recommended, no

capris• Socks• Covered arms (see above)

NOTE SHEETwww.soinc.org

Part 1: Qualitative AnalysisIn the past, this has been the worst performance section. For SCB this part is 50% of the score (only 20% for FOR).

How to do it:• Knowing what is in your kit, how to use it and what it tells

you is very important. Get all the things and have them. That includes your note sheet.

• SCB mixtures: use a magnifying glass at first to try to visually test.

• Many of the substances are translucentcrystals, seeing dissolution on a white plate is very hard. Try to acquire clear plastic or glass dished for your teams to work with.

http://sciencekit.com/plates-and%23038%3B-spot-plates/c/3286/

Part 1: Qualitative AnalysisHow to prepare:• Method 1: Obtain all the potential chemicals form the list,

use every technique available on each chemical and record the results. This can be a brute force table approach or be incorporates into a flow chart.

• Method 2: “Steal” a flow chart from the internet.• Neither of these substitutes for the experience of seeing

and interpreting the results that comes from practice.

Part 1: Qualitative AnalysisResources:• Sciencekit.com and other supply houses sell chemicals and

equipment, WSU, your local university or high school science department.

• Study materials on how to do tests:•

FOR--http://soinc.org/sites/default/files/uploaded_files/qualhints.pdf http://soinc.org/sites/default/files/uploaded_files/forensics/For_ForensicsQualReactions.pdf

• SCB-- http://soinc.org/sites/default/files/uploaded_files/crimebusters/Individual%20Solid_Nonmetal_analysis.pdfhttp://soinc.org/sites/default/files/uploaded_files/crimebusters/Liquid_analysis.pdf

Part 2: Polymer TestingHair identification:

SCB: human, cat, dogFOR: bat, horseHairs presented as images; Know scales and medullas

Fiber identification:SCB: animal, vegetable, syntheticFOR: cotton, wool, silk, linen, spandex, polyester Samples presented as images and pieces of fabric; Microscopic appearance (how they burn for FOR)

Polymer identification:SCB: PETE, HDPE, PS, LDPE, PP, PVCFOR: PC, PMMASamples likely presented in text format; Know density ranges and burn test results

Part 3: Paper ChromatographyThis is a relatively simple experiment to perform and interpret, yet is still the second most poorly performed section. However, it is not the most highly weighted experiment.

How to do it:

Lets give it a try.

This is also about visual and quantitative comparison of the spots that are observed. SCB—you will do strict visual comparison of the patterns/colors obtained form the test. FOR—you may be asked to include calculations of retention factors to “prove your point” (spot distance/solvent distance)

Part 3: Paper ChromatographyHow to prepare:

http://www.yesmag.ca/projects/paper_chroma.htmlhttp://soinc.org/sites/default/files/uploaded_files/forensics/For_Chromatography2.pdf

Get some paper towels, filter paper, coffee filters, absorbent art paper, something that is going to wick water via capillary action.Get cups, beakersGet pens (not gel pens), water color paints, M&Ms, Kool-aid and do it.

Part 4: Physical EvidenceMany possibilities:• Blood spatter evidence• Fingerprints• Shoe/tires• Fingerprints• DNA• Glass• Entomology• Seeds/pollen• Blood type• Bullet striations

Part 4: Physical EvidenceFingerprints:• 3 pattern types (arch, loop, whorl) SCB• Each has subtypes FOR

• Plain arch, tented arch• Ulnar loop, radial loop• Plain whorl, central pocket loop whorl, double loop

whorl, accidental whorl• Identify deltas, identify ridge flow• Types of minutiae points• Types of development

Part 4: Physical EvidenceBlood stains• Blood stains identify their direction of travel• Round/circular stains landed perpendicular to the surface• Oval stains have a tail that points in their direction of

travel, opposite their point of origin (asin Θ = W/L)• Size is relative to force (velocity)

Part 4: Physical EvidenceDNA• Students must be able to interpret DNA separations to

determine possible donors• FOR students need to be able to discuss the PCR process

Shoe/Tire• Students must be able to match shoe and tire tracks based

on pattern comparison and individual characteristics

Part 4: Physical EvidenceFOR Event only

Seeds/Pollen• Just need to look at pictures, visual comparisons

Soil• Wet and dry color comparison if allowed

Bullet striations• Just need to look at them again

ABO blood typing• Conceptually is very easy to accomplish with a few

materials, we may do this this year• Additionally, there is a place for blood cell species id based

on visuals

Part 4: Physical EvidenceGlass• Refractive index is the amount that light bends, you can do

numerical comparisons• Glass fractures do not cross other glass fractures, tells you

which crack was there first• High impact in glass cones out the exit side

Entomology• Insect arrival ordering,

http://www.clt.uwa.edu.au/__data/page/112507/fse07_forensic_entomology.pdf

Part 5: Analysis of the CrimeMost important part of the whole event

Need to leave plenty of time to write it up

Who and WHY!!!!

Who and WHY NOT!!!!

Criminal justice is about proof, forensics is about identification and the strength of the association

Developed a rubric to grade on: neatness, grammar, spelling, clarity of thought, correct associations, correct conclusions are all a part of the score.

Practice two things: evidence X has this some level of significance; person Y because

Science is Fun……but only if you know something.

The students that enjoy the event the most and the ones that come prepared. Otherwise it is 50 minutes of frustration.

Many of the activities in these events are qualitative and descriptive, but are also great ways of getting students to reason through the logical processes of scientific discovery (read: problem solving)