White Powder Test.

White powder test?

A forensic scientist may discover powder at a crime scene. In order to determine if it is illegal or not the crime lab will identify the substance using chemistry. Take on the role of a forensic chemist to identify unknown substances.

Become a Forensic Chemist by following these procedures and filling in the Powder Analysis Chart with your results. 

Complete the appearance, texture, and smell activities before opening the vinegar and iodine bottles.

Record your findings in the Powder Analysis Chart below.

Aim: To determine how different powders feel, look and react to other substances.

Hypothesis: I expected everything to dissolve to both liquids.

Equipment:

Baking Soda
Cornflour
Sugar
Salt
Iodine
Vinegar
Magnifying glass
Eyedrop
Black card
Tea spoon / stick

Method: 

1. Place one-fourth teaspoon (1 ml) of the four white powders on a sheet of black construction paper. Label the powders with your pen.
2. Study the powders with the magnifying glass. Examine what each powder looks like. How would you describe the powder's shape. Does it have large or small grains? Your observations should be written in the appearance column of the chart.
3. Examine the powders further by rubbing each powder between your fingers. Describe how each powder feels in the Texture column of the chart.
4. Determine if there is a smell to any of the powders. Record your findings in the Smell column of the chart.
5. Take the eyedropper and place a drop of water on each individual powder. Examine what happens? Do the powders dissolve? Is there a reaction? Write your observations in the Reaction to Water column.
6. Place one-half teaspoon (2ml) of each powder in a separate jar. Add 2 drops of iodine to each jar using the eyedropper. Record what happens in the Reaction to Iodine column. Iodine should be handled with care.

Findings:  Only certain liquids dissolve certain powders. I found this interesting.

Powder Analysis Chart

                                                                                                  
Substance          Appearance   Texture    Smell     Water     Vinegar     Iodine

Cornflour = B -         Small          Smooth  No Smell   Dissolves                  Doesn't dissolve

Sugar = D -              Large         Course   No Smell   Dissolves                   Doesn't Dissolve

Salt = C -                  Medium        Fine       No Smell  Dissolves                 Doesn't Dissolve

Baking soda = A -     Medium        Fine      No Smell   Dissolves                Dissolves

Summary: Baking Soda is the most vulnerable to dissolving, and Sugar have the largest powders of all four.