Name: ______

Date: ______

Period: ______

Purpose: To investigate the movement of water into and out of Gummi Bear.

Problem: Where is the concentration of H₂O molecules highest, tap water, salt water, or Gummi bears?


Hypothesis:

If the H₂O concentration in tap water is (higher, lower) that the H₂O concentration in a Gummi Bear, then the Gummi Bears placed in tap water will (Increase, decrease, remain the same) size. Circle your answer.

Because: ______

Procedures:

1. Obtain two beakers, two different colored Gummy Bears and a ruler.

2. Label your beaker with a piece of masking tape.

3. Write your group number on the tape.

4. Label one beaker with water and the other with salt water.

5. Measure your bear (in cm) from top to bottom (length) and from side to side (width) and from front to back (height).

6. Record the dimensions in centimeters in the data table. Use decimals.

7. Find the mass of each bear. Record the mass in the data table in grams. Again, use decimals.

8. Weigh your Gummi Bears on the electronic scale in grams and record.

9. Place the bears in the beaker.

10. Cover the bear with water. The bears should be completely covered- beaker half way full.

11. Cover the other bear in the second beaker with water. The bear should be completely covered and resemble the first beaker. Add 10 ml of salt in the beaker. Stir.

12. Place bear on the counter away from direct sunlight.

13. Let them sit over night.

14. On the next day, gently pour the water out over a screen or paper towel and catch Gummi bear.

15. Be careful not to break apart the bear, they are fragile.

16. Blot it dry and place it on a table matt provided.

17. Find the mass of the bear and record.

18. Weigh and record in grams. Record.

19. Find the volume of your bear. (LxWxH).Round your answer to the nearest hundredth.

Data Table for Volume:

Dimensions / Tap Water / Salt Water
Initial
Before Soaking / Final
After Soaking / Initial
Before Soaking / Final
After Soaking
Length(cm)
Width (cm)
Height (Cm)
Volume (cm³)
LxWxH= ____ cm³

Data table for Mass:

Mass in Grams / Tap Water / Salt Water
Initial
Before Soaking / Final
After Soaking / Initial
Before Soaking / Final
After Soaking
Gummi Bear Mass

Data Table for Weight:

Weight in Grams / Tap Water / Salt Water
Initial
Before Soaking / Final
After Soaking / Initial
Before Soaking / Final
After Soaking
Gummi Bear Mass

Analysis Questions:

Answer the following using complete sentences, Be sure to restate your answers.

1. What happened to the bears when placedin water? Why?

______

2. What happened to the bears when placed in the salt water? Why?

______

3. What do you believe would happen to the bear placed in salt water if if=t was again placed in to tap water?

______

7. Conclusions: (6 points)

Write a paragraph which explains the results of this experiment using the concept of osmosis. Think about how much swelling can occur (equilibrium) Include your specific data to explain your results and support conclusions.

______