Crime Scene Lab

Only available on StudyMode
  • Download(s) : 91
  • Published : November 12, 2010
Open Document
Text Preview
Susanna Skalikeu
10-6-10
Science
Period 4
Crime Scene Investigation
Background:
The only evidence from the crime was a whitish powder found on the floor. There are three main suspects. The first is Anne Fryer. She uses corn starch (a whitish powder) as the secret ingredient in her stir fry recipe. Bobby Brulee uses baking soda (also a whitish powder) to make his special deserts. Charlie Croissant uses baking powder (also a whitish powder) all the time to fluff up his bread.

Question:
How can you find out who killed the owner… Anne Fryer, Bobby Brulee, or Charlie Croissant?

Observations:
Mr. Brulee’s powder seemed to match the most with the powder form the crime scene. It was the same color and it looked like it had the same texture. Its color was whiter than the rest and its texture was smoother and less bumpy than the other substances.

Hypothesis / Prediction: If you where to test the chemical properties of each substance, then you will find that baking soda matches the substance found at the crime scene because of the physical properties we observed in our observations, baking soda matched the best to the powder found at the crime scene.

Variables:
Manipulated Variable: Type of Liquid.
Responding Variable: Chemical reactions.
Controlled Variable 1: Amount of liquid drops into each sample of powder. Controlled Variable 2:

Materials:

Water - compound
Vinegar – solution (homogeneous mixture)
Potassium Iodine - compound
Corn starch – homogeneous mixture
Baking soda - compound
Baking powder – homogeneous mixture
Micro well
Dropper

Procedure:
1) Gather all materials.
2) In the first vertical row, using a spatula, put the substance found in the crime scene in three vertical holes. 3) In the second vertical row, using a spatula, put baking powder in the three vertical holes. 4) In the third vertical row, using a spatula, put baking soda in the three vertical holes. 5) In the fourth vertical row, using...
tracking img