SC.4.P.9.1 Changes in Matter Stations Adapted from 730 Easy Science Experiments (1997) Exploring Chemical Changes Department of Science

Station 1 Copperhead Procedures: 1.In a cup, make a solution with salt and water; pour vinegar in another cup. 2.Place the coins on the paper towel. 3.With the medicine dropper, drop the salt solution on the pennies followed by the vinegar. 4.Repeat these steps and keep the pennies in the solution for five minutes. 5.Clean the pennies by wiping them off with a damp paper towel. 6.Record your observations. Materials: dark, dull copper coins small, flat container 2 disposable cups 5 mL (1 teaspoon) of salt 15 mL (1 tablespoon) of water 30 mL (2 tablespoons) of vinegar Medicine dropper Paper towel Department of Science

Station 1 Copperhead Department of Science Record your Observations How did the pennies react when salt, water, and vinegar solution was applied to them? What did the pennies look like before the solution was applied? What did the pennies look like after the solution was applied? Did the solution of water, salt and vinegar form a new product(s)? Provide your evidence.

Station 2 Exothermic Exercise Procedures: 1.Record the temperature showing on the thermometer. 2.Place the thermometer in the bowl. 3.Pour in the hydrogen peroxide. 4.Add the yeast and stir the solution. 5.As you watch what happens, feel the lower sides and bottom of the bowl. 6.Wait a minute or two; then take out the thermometer and record the temperature again. 7.Record your observations. Materials: Thermometer Small bowl 5 mL (1 tablespoon) of quick-rising yeast 60 ml (¼ cup) of hydrogen peroxide Spoon Department of Science

Record your Observations 1.What happened when the quick-rising yeast was added to the hydrogen peroxide? 2. What sign(s) of a chemical change taking place was evidence? 3. Identify the change in temperature that resulted in the exploration. Station 3 Exothermic Exercise Department of Science

Station 4 Endothermic Cold Wave Procedures: 1.Fill the jar with tap water. 2.Place the thermometer in the water. 3.With your hand, feel the coolness of the jar while you wait until the thermometer registers the water’s temperature. 4.Record the temperature. 5.Stir in the Epsom salts. 6.Feel the jar again. 7.After a couple of minutes, take out the thermometer and record the temperature again. 8.Record your observations. Materials: Thermometer 5 mL (1 tablespoon) of Epsom salts Tap water, room temperature Spoon Medium-size jar Department of Science

Record your Observations 1.How did the temperature of the thermometer change as the Epsom salt was stirred in the water? 2.Based on what you have observed, how can you relate what happened in this exploration to the real world? 3.Can you identify signs of a chemical change taking place based on your qualitative data? Station 3 Endothermic Cold Wave Department of Science

CER Conclusion Writing How can you recognize if matter has undergone a chemical change? Claim: (The answer to the question) Evidence: (All the evidence you gathered from hands-on investigations.) The evidence includes the clues: the data collected and the observations made. Reasoning: (Why you think the answer is correct.) The reasoning explains how the evidence helps answer the question. Department of Science

CER Conclusion Writing How can you recognize if matter has undergone a chemical change? Claim: Sample answer Matter has undergone a chemical change when its properties change to form a new substance. Department of Science

CER Conclusion Writing How can you recognize if matter has undergone a chemical change? Evidence: Sample Answer The data collected in the explorations showed the following: in station 1, the dark and dull film of the penny was removed after 5 minutes when soaked with water, salt and vinegar solution. The penny returned to its shiny-bright copper color. In station 2, foams, bubbles were observed, and the bottom and sides of the bowl feel very warm after mixing the rising yeast and hydrogen peroxide solution. In addition, the thermometer reading shows that heat was produced because the temperature increased by ____ degrees Celsius. In station 3, … Department of Science

CER Conclusion Writing How can you recognize if matter has undergone a chemical change? Reasoning: Sample Answer A change in temperature (increase or decrease), a change in color, formation of bubbles, of matter are all signs of a chemical change. The data collected from the explorations support the claim that matter has undergone a chemical change since its properties changed to form a new substance. Department of Science