Evidence Evaluation from the Crime Scene CSI Agents: Salil K. Julianna I. Leah H. Kristin H.

Physical Properties A physical property is a characteristic of matter, and does not change the chemical makeup of a substance.

Example of Physical Properties  Color  Odor  Density  Viscosity  Mass  Transition points  Ductility  Malleability  Texture  Conductivity, etc.

Chemical Properties  A chemical property is a characteristic of matter.  It’s a property that describes a substance or substances chemical makeup.  It cannot be determined by your senses, but must be changed in some sort of chemical way.  It is an ability to react with other substances.

Examples of Chemical Properties  Flammability  Combustion  Oxidation  Heat of Combustion  Electromotive  Reactivity with water  reactivity with vinegar  Reactivity with iodine  Etc.

Magnetic Metal Evidence Evaluation Steel Aluminum

Metal Evidence Evaluation Identity of Sample 1 is : Aluminum Supporting evidence:  Non-magnetic  Density – 2.5 g per mL  Silver colored  Mass = 3.8 grams  Length = 4.7 cm  Volume = 1.5 mL

Metal Evidence Evaluation Identity of Sample 2 is : Steel Supporting evidence:  Magnetic  Color is brown  Density – 7.85 grams per mL  Mass – 2.3 grams  Volume – 1 mL  Length – 4 cm

Liquid Evidence Evaluation  Evidence X- Water, Alcohol, or Vinegar  Based on the evidence and our observations, we have concluded the liquid is alcohol due to the fact that all of the test results match up exactly for the mystery liquid and the alcohol

Physical PropertiesChemical Properties Mystery Liquid Properties  Clear  Mass: 17 g  Volume: 20 mL  Density: 0.85 g per mL  Odor is alcoholic  Flammable

Mystery Liquid Evidence Mystery Liquid Video watch?v=a3x0UDU5zQc Burning Alcohol Video watch?v=_dG3OX0FFkI “Burning” Water Video watch?v=1oeEumV7yx8 “Burning” Vinegar Video watch?v=6MJXOtFMTDI

Powder Evidence Evaluation WaterVinegarIodine Baking powderRises Bubbles Fizzes Turns black Baking sodaNo reactionBubbles Fizzes No reaction Corn starchNo reaction Turns black Baby powderBubble of water hydrophobic Bubble of vinegar No reaction Mystery powderRises bubbles Bubbles Fizzes Turns black

Summary of Findings We conclude that the materials found at the A West crime scene were: The mystery metals was: The mystery liquid was: mmmmm The mystery powder was: hjdhdh

Mystery Samples

Steel Aluminum Metals Identity

Results