Based on the information provided, let's evaluate each of the statements for potential truthfulness.
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Burning campfire wood is a chemical change. - True. Burning wood involves combustion, which transforms the wood into ash, smoke, and gases (carbon dioxide and water vapor), indicating a chemical change.
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Toasting marshmallows results in a chemical change. - True. When marshmallows are toasted, the sugars caramelize and the proteins undergo Maillard reactions, leading to changes in flavor and texture, which are chemical changes.
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Burning campfire wood is a physical change. - False. As explained above, burning wood is a chemical change.
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Toasting marshmallows results in a physical change only. - False. Toasting marshmallows involves both physical changes (like melting) and chemical changes (like caramelization and Maillard reactions).
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The heat produced by the fire chemically changes the surrounding air. - False. While the heat can lead to chemical processes (like combustion), the heat itself does not chemically change the air. It can change the temperature and state but not the chemical composition without a reaction occurring.
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The heat produced by the fire physically changes the surrounding air. - True. The heat can cause the air to rise, change temperature, and possibly create convection currents, which are physical changes.
In summary, the true statements from the list are:
- Burning campfire wood is a chemical change.
- Toasting marshmallows results in a chemical change.
- The heat produced by the fire physically changes the surrounding air.
11 answers