Gummy Bear Lab Name:

Objective:

What happens to the volume of a Gummy Bear after being submerged in various types of water?

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Background Information:

Gummy Bears are made of gelatin and sugar. Gelatin is a poymer that forms large three-dimensional matrices which give structural support to jellies and jams, and lots of other things that you use every day. Essentially, Gummy Bears are mostly air, sugar, and gelatin.

Distilled water is water that has been boiled, then re-condensed. When it boils, everything other than pure water is left behind. So when the pure water vapor condenses it should be pure water (no impurities in it).

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Hypothesis:

  1. What do you think will happen to the volume of a gummy bear that has been submerged in regular water for two days? Why?
  1. What do you think will happen to the volume of a gummy bear that has been submerged in distilled water for two days? Why?
  1. How do you think the volume of the gummy bear in distilled water will compare to the volume of the gummy bear in regular water? Why?

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Materials:

·  2 plastic cups (8oz)

·  Permanent marker

·  2 aluminum or plastic screens

·  2 Gummy Bears (different colors preferably)

·  Distilled water

·  Tap Water

·  Ruler

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Procedure:

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

2.  On the side of each cup write your class period and the names of the people in your group.

3.  Label one cup “TAP WATER” and the other cup “DISTILLED WATER”.

4.  Measure both of your bears (in cm) from top-to-bottom (height), from side-to-side (length), and from front-to-back (width).

5.  Record your measurements and the calculated volume for each bear in the data table (use decimals up to the nearest tenth place).

6.  Place the bears in the cups and cover one with distilled water, the other with tap water.

7.  Place the cups on the counter away from direct sunlight, and let them sit until next class.

8.  During the next class period, gently pour the water over a screen into the sink. Catch each bear on a separate screen. While on the screen, measure the bear’s height, length, and width, and record their measurements and calculated volumes in the data table. BE CAREFUL not to break the bears, they are very fragile.

9.  Place the bears back into their correct cups.

10.  Cover the bears with a saturated salt water solution and let them sit until next class.

11.  During the next class period, gently pour the water over a screen into the sink. Catch each bear on a separate screen. While on the screen, measure the bear’s height, length, and width, and record their measurements and calculated volumes in the data table. BE CAREFUL not to break the bears, they are very fragile.

12.  Discard the gummy bears (you do not want to eat these bears) in the garbage, pour the salt water solution down the sink, and clean up any water.

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Data Table:

Gummy Bear in tap water

Height (cm) / Length (cm) / Width (cm) / Volume (cm3)
Before any water
After tap water
After Salt Water

Gummy Bear in distilled water

Height (cm) / Length (cm) / Width (cm) / Volume (cm3)
Before any water
After distilled water
After salt water

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Analysis of Data:

  1. Calculate the percent change in volume for both bears after being submerged in tap and distilled water for two days. Percent change = ((final volume – initial volume) / initial volume) x 100.

Ex: ((50-30) / 30 ) x 100 = (20/30) x 100 = 0.67 x 100 = 67%

Gummy Bears / % Change in water
Tap Water Bear
Distilled Water Bear
  1. Calculate the percent change in volume for both bears from coming out of their tap or distilled water baths to after coming out of their salt water baths. Percent change = ((final volume – initial volume) / initial volume) x 100.

Gummy Bears / % Change in salt water
Tap Water Bear
Distilled Water Bear
  1. What happened to the bears after sitting in water for the first couple days?
  1. Why did the volumes change this way after being submerged in water?
  1. How did the volume of the bear in distilled water compare to the volume of the bear in tap water after a couple days being submerged?
  1. What caused the difference in the volumes from the last question?
  1. What happened to the volumes of the bears after being submerged in salt water for a couple days?
  1. Why did the volumes change this way after being submerged in salt water?
  1. What do you think would happen to the bears if they were again placed in distilled water for two days after coming out of the salt water solution? Why?

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Claim – Evidence – Reasoning:

·  What claim are you making with the results of your experiment? (answer the question “What happens to the volume of a Gummy Bear after being submerged in various types of water?” in paragraph form).

·  Explain the specific evidence from your experiment that back up the claim you just made.

·  Why does your evidence support your claim? (Write about any scientific principles that would also back up your claim. Make sure to explain these scientific principles to show how they affected your Gummy Bears).