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Bag of Change

Purpose:

To practice observing and identifying physical and chemical changes. Materials:

Chemical A - white solid Chemical B - white solid Chemical C - blue liquid

Small graduated cylinder Ziploc bag Small beaker Procedure: Parti

Describe and record the properties of chemicals A, B and C. Observations should include the color, state and texture of each chemical.

Mix one spoonful of chemical A, one spoonful of chemical B and lOmL of chemical C in a Ziploc bag and quickly seal h up.

In the first 30 seconds, squeeze the bag in various places to mix the chemicals. Detect any temperature changes with your hand. Record as many observations as you can. When fmished, wash all chemicals down the drain, rinse out the plastic

bag and then put it in the garbage. Part 2

In a small beaker, mix one spoonful of chemical A and chemical B. Record your observations.

Rinse out and dry your beaker, and mix one spoonful of chemical A with 5mL of chemical C. Record your observations.

Rinse out and dry your beaker, and mix one spoonful of chemical B with 5mL of chemical C. Record your observations.

Clean all glassware and put all materials away.

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Observations; P a r t i

Initial Observations

Final Observations

Part 2

Chemical A & Chemical B

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Chemical A & Chemical C

Chemical B & Chemical C

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C )

Conclusion:

Questions:

1. List and describe the changes that you observed in the plastic bag.

o ) 2. Which observations were physical changes and which were chemical changes?

3. Based on Part 2 of your experiment, which chemicals were responsible for the

changes observed in Part 1? Why do you think this?