Unknown Crime Scene Evidence Identification

PBL #1

S8P1d. Distinguish between physical and chemical properties of

matter as physical (density, melting/boiling

point) or chemical (reactivity,

combustibility).

CSI agents frequently find substances and

items at crime scenes and must identify them.

The agents use the properties of the

substances to guide them to an identity of

this matter.

ProblemYour team is being called as CSI expert witnesses at a trial. You need to prepare a presentation to prove to a jury the identity of the evidence (matter) found at a crime scene. Use your expertise of physical & chemical properties in your presentation.

A white powderA clear liquidA metal

The evidence found at the crime scene that you must identify:

The white powder is one of the following:1. Baking

soda2. Baking

powder3. Baby

powder4. Cornstarch

The clear liquid is one of the following:1.Water2.Isopropyl

alcohol3.Hand

sanitizer

The metal is one of the following:1.Copper2.Aluminum3.steel

Since you are CSIs in training, your CSI trainer has provided you with some preliminary findings.

The identity of each substance based on the data collected from your observations and experiments

The physical properties used to identify each How you used the physical properties to

differentiate between the possible substancesThe chemical properties used to identify eachHow you used the chemical properties to

differentiate between the possible substances Pictures that support your findings

Your presentation must include:

You will be cross-examined,

so be………

PREPARED!!