Chapter 3 Resource: Matter and its Changes

Name Date Class
Laboratory Activity 2 (continued)
Hands-On Activities
Part C
1. Dissolve 1/2 spoonful of Epsom salts in a test tube of water.
2. Dissolve 1/2 spoonful of washing soda in another test tube of water.
3. Observe what the mixtures in both test tubes look like.
4. Begin pouring the Epsom salts mixture into the petri dish near one edge of the dish.
5. At the opposite edge of the petri dish, begin pouring the washing soda mixture into the dish.
6. Observe what happens where the two mixtures meet. Record your observations in the table in the
Data and Observations section.
Part D
1. Place a dull, copper penny in the bottom of a petri dish.
2. Sprinkle salt over the top of the penny. Then use a dropper to cover the top of the penny with
vinegar. Observe any changes in the penny. Record your observations in the table in the Data
and Observations section.
Data and Observations
Substances
Changes you observed
Baking soda, calcium
chloride, and water
Cornstarch, water,
and iodine
1.
2.
Epsom salts, washing
soda, and water
Copper penny, salt,
and vinegar
3.
4.
Questions and Conclusions
1. Identify four signs that indicate that a chemical change has taken place.
2. In Part A, what evidence did you observe that a chemical change took place
3. In Part B, what evidence did you observe that a chemical change took place
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14 Matter and Its Changes