Pop Can, Chocolate Bar and Baking Soda/Candle: Demonstration
Name: ______
Date: ______
Purpose: To view and experience chemical and physical changes.
Pop Can
Hypothesis: (What do you think will happen to a pop can filled halfway with boiling water when it is placed upside down in a pan of cold water?) ______
Materials:
Procedure:
1. Pull your chair around the table so that you can see. Ensure that you are at least 2 meters away.
2.Your teacher will pour water into an empty pop can (about halfway).
3.The pop can will be held over the burner until the water boils.
4.As you are waiting, discuss what you think is going to happen.
5.Once the water is boiling, the teacher will quickly turn it upside down and place it into the pan of cold water (be careful, water may splatter).
Observations:
Describe what happened and draw a picture.
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Question:
Was this a physical change or a chemical change? How do you know?
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Chocolate Bar
Hypothesis: (What will happen when chocolate is heated?) ______
Materials:
Procedure:
1. Pull your chair around the table so that you can see. Ensure that you are at least 2 meters away.
2.Your teacher will heat the Hershey bar in the saucepan.
3.Once it is melted you may be able to taste the chocolate.
4.Continue heating the chocolate.
5.Once is it burnt, you may be able to taste the chocolate.
Observation: (write down everything you observe with each of your five senses)
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Questions:
Was the melted chocolate a physical change or a chemical change? How do you know?
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Was the burnt chocolate a physical or a chemical change? How do you know?
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What other substances could we do this same demonstration with?
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Baking Soda, Vinegar and a Candle
Hypothesis: (What will happen when we try to light a candle after the reaction between vinegar and baking soda?) ______
Materials:
Procedure:
1. Pull your chair around the table so that you can see. Ensure that you are at least 2 meters away.
2.Place the candle inside a bowl. Sprinkle five tablespoons of baking soda around the candle.
3. Next light the candle and spoon vinegar down the side of the bowl. The mixture will bubble. Stop spooning in vinegar once the mixture reaches halfway up the candle. The candle will go out.
4. Try to relight it – observes what happens
5. Wait 2 minutes and try to relight – what happens now?
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Observations:
Describe what happened and draw a picture.
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Describe what happens when you try to relight the candle:
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Describe what occurs after 2 minutes when you try to relight:
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Question:
Was this a physical change or a chemical change? How do you know?
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Why would the candle not relight?
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