+

CSI Evidence Evaluation of the Grapefruit Crime Scene

Agents:Peter UdallCole TysonJennifer 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 Propertieso 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

oOxidation: The ability of a substance to react with oxygen.

oCorrosion: The breaking down of a substance based on it’s chemical surroundings.

oFlammability: The ability of a substance to burn

+Metal Evaluation

Metal Sample 2

Metal Sample 1

+Metal Evaluation

Metal Sample 1

Metal Sample 2

+Metal Evaluation

SteelAluminum

+Metal Sample 1

Non-magnetic

Silver in color

Mass: 1.6g

Volume: .5 cm3

Density: 2.7 g/cm3

http://terpconnect.umd.edu/~wbreslyn/magnets/is-aluminium-magnetic.html

+Metal Sample 2

Dark grey

Magnetic

Mass 2.6g

Volume .25cm3

Density: 7.85g/cm3

+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

+Mystery Liquid Comparison

+Conclusion

The liquid is rubbing alcohol.

+Powder Evaluation

H20 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 water, vinegar, and iodine, it had the same reaction as

the baking powder.