csi evidence evaluation of the grapefruit crime scene agents: peter udall cole tyson jennifer shen...
TRANSCRIPT
CSI Evidence Evaluation of the Grapefruit Crime Scene
Agents:Peter UdallCole Tyson
Jennifer ShenJoanna Tolentino
Physical Properties
Definition: Physical properties are properties of matter that can be judged by observing the
matter or it’s measurements.
Examples of Physical Properties
o Density: The amount of mass in a certain amount of space.
o Volume: The amount of three-dimensional space in an enclosed area.
o Ductility: The ability of a substance to stretch into a wire and retain it’s position.
o Malleability: the ability of a substance to be pressed into sheets.
o Magnetism: The ability of a substance to conduct with magnets.
o Color: The pigment of an object
Chemical Properties
Definition: Properties that are only observable during chemical reactions.
Examples of Chemical Properties
o Oxidation: The ability of a substance to react with oxygen.
o Corrosion: The breaking down of a substance based on it’s chemical surroundings.
o Flammability: The ability of a substance to burn
Metal Evaluation
Metal Sample 2
Metal Sample 1
Metal EvaluationMetal Sample 1 Metal Sample 2
http://terpconnect.umd.edu/~wbreslyn/magnets/is-aluminium-magnetic.html
Metal Evaluation
SteelAluminum
Metal Sample 1
• Non-magnetic• Silver in color• Mass: 1.6g• Volume: .5 cm3• Density: 2.7 g/cm3
Metal Sample 2
• Dark grey• Magnetic• Mass 2.6g• Volume .25cm3• Density: 7.85g/cm3
http://terpconnect.umd.edu/~wbreslyn/magnets/is-aluminium-magnetic.html
Conclusion
• Metal sample 1 is aluminum• Metal sample 2 is steel
Liquid Evaluation
• The liquid was either water, liquid, or alcohol
Alcohol
Vinegar
Water
Mystery liquid
Conclusion
• The liquid is rubbing alcohol.
Powder EvaluationH20 Vinegar Iodine
Baking Powder
• Soluble• Milky
substance
• Bubbles up
• Turns black• Absorbent
Baking Soda • Highly soluble
• Turns Cold
• Bubble/explode
• Stayed brown
• Absorbent
Corn Starch • Low solubility• H20 slides off
• No bubbles
• Turned black• Absorbent
Baby Powder • Hydrophobic • Not soluble
• No bubbles
• Every low solubility
• Slides off stays brown
Mystery Powder
• Soluble • Milky
substance
• Bubbles up
• Turns black• absorbent
Baking Powder
Baking Soda
Corn Starch
Baby Powder
Mystery Powder
Mystery powder comparison
Powder conclusion
The powder was baking powder because when it was exposed to vinegar it had the same reaction as the baking powder, and when exposed to iodine it turned black like the baking powder.