Presentation on theme: "Physical and Chemical Changes Notes Pages 78-87. 1. Define physical change. Give an example of a physical change. A change in which the form or appearance."— Presentation transcript:
1. Define physical change. Give an example of a physical change. A change in which the form or appearance of matter changes, but not its composition. Examples: water changes to ice.
2. Generally, how can you cause a physical change? Cut, tear, grind, bend matter
3. Why is dissolving a physical change? Give an example to support your answer. The dissolved substance does not have its composition changed. Sugar dissolving in tea.
4. Why is a change of state a physical change? Give an example to support your answer. The substance does not change its composition. Ice changes to water.
5. Define a chemical change. Give an example of a chemical change. A change in which the composition of a substance changes. Example: Rust
6. Page 80, answer the reading check. A chemical change alters the composition of the matter, while a physical change alters appearance but not composition.
7. A change in color is a chemical change. Give an example to support this statement. A half eaten apple exposed to air turns brown.
8. How can you tell if an energy chemical change has occurred? There will be a change in temperature (change in thermal energy)
9. What chemical change can occur with spoiled foods? A change in odor will occur.
10. The formation of a gas is a clue to a chemical change.
11. The formation of a solid out of a solution is a chemical change.
12. The substances produced during a chemical change cannot be changed back into the original substances by physical means.
13. What six signs indicate a chemical change? 1.Change in color 2.Change in energy 3.Change in odor 4.The formation of a gas 5.The formation of a solid 6.The substance cannot change back to its original composition.