Where's That Odor?

Purpose: To apply science inquiry skills and sharpen observation skills

Materials

• liquid measuring cup
• 6 shallow plastic containers with lids (old butter bowls)
• vanilla extract
• ¼ cup of water
• nail polish remover (pink in color)
• food coloring (blue, red, yellow)
• graphing paper
• 2 pieces of notebook paper
• colored pencils
• stopwatch
• Data Collection Chart

Procedure

Material Preparation

1. With adult supervision, mix 8 small drops of blue, red, and yellow food coloring in a measuring cup to make a decoy vanilla extract.
   • Vanilla extract looks brown. Be careful with the food coloring; it stains!
2. Pour a small amount of this decoy mixture into two separate container lids and set it aside in a safe place.
   • Pour just enough in each to cover the lid surface.
3. Mix 3 small drops of red food coloring into ¼ cup of water and stir until it looks light pink to make a decoy of nail polish remover.
   • It may take some extra water or red food coloring to get a close match to the nail polish remover you are using!
4. Pour a small amount of this decoy mixture into two separate container lids and set it aside in a safe place. You have used four of the six container lids so far!
5. Take the last two lids and add the real vanilla extract to one and the real nail polish remover to another. Remember to pour just enough in each to cover the lid surface.
6. Gently place plastic bowls over the six container lids to act as a cover!

Preparation for Participants in the Investigation

1. Share the idea of the investigation: Record when participants first smell an odor and measure how strong it is every thirty seconds.
   • Give each person in the investigation a piece of graphing paper and go over the directions printed with the Data Collection Chart.
2. Remove the covers from each of the six container lids carefully, start the timer, and quickly get to a location in the room where all investigators can hear you.
3. Begin the 2-minute countdown and call out the time. Call out 30 seconds, then 60 seconds, then 90 seconds etc. until the 2 minutes are up!
4. At the end of the 2 minutes, recover all the container lids.
5. Investigators should report findings and record the information on the group data collection table.

Data Collection Chart

The Intensity levels
1 - No odor     2 - Slight odor     3 - Strong odor     4 - Very strong odor

	0 Seconds	30 Seconds	60 Seconds	90 Seconds	120 Seconds
Investigator 1
Investigator 2
Investigator 3
Average Intensity of A-E	Average of A	Average of B	Average of C	Average of D	Average of E

Investigation Directions to Share With the Participants

1. Assign each investigator a position in the largest room of the house.
2. Investigators will draw on the map where they are in the room and include surrounding furniture, stairways, and doorways.
3. After the mixtures are uncovered in various positions around the room, the time will be called out in 30-second intervals for a total of 2 minutes.
   • For example: After 30 seconds say, "Time is now 30 seconds."
4. Investigators will record the information on the Data Collection Chart.
5. Once the observation time is complete, participants are to find their place on the map and fill in the letter and intensity rating of the first odor they smelled. If more than one odor is detected, fill in the letter and intensity number for each.
6. After the time is up, each person will report the information to the investigation leader.

Conclusion

1. Why did some investigators record stronger odors sooner than others?
2. Did the odor move in one direction more than another?
3. Did anyone detect more than one odor?
4. Where did the odor(s) come from?
5. What do the data suggest about the way pollutants move in air?
6. How can this information help?