📚 Topic Summary
Phase changes are physical processes where matter transitions between solid, liquid, and gaseous states. These changes occur when energy is added or removed from a substance, altering its temperature and causing the molecules to rearrange. Common phase changes include melting (solid to liquid), freezing (liquid to solid), vaporization (liquid to gas), condensation (gas to liquid), sublimation (solid to gas), and deposition (gas to solid). Understanding these transitions is crucial for grasping many chemical and physical phenomena.
🧪 Part A: Vocabulary
Match the terms with their correct definitions:
| Term | Definition |
|---|
| 1. Melting | A. The change of state from a gas to a liquid. |
| 2. Condensation | B. The change of state from a solid to a gas. |
| 3. Sublimation | C. The change of state from a liquid to a gas. |
| 4. Freezing | D. The change of state from a liquid to a solid. |
| 5. Vaporization | E. The change of state from a solid to a liquid. |
💧 Part B: Fill in the Blanks
Complete the following paragraph using the words: energy, temperature, boiling point, kinetic, phase change.
During a __________, the __________ of a substance remains constant even though __________ is being added or removed. This added or removed energy changes the __________ energy of the molecules, facilitating the transition. For example, when water reaches its __________, adding more heat doesn't increase the temperature; instead, it converts the liquid water into steam.
🤔 Part C: Critical Thinking
Explain how intermolecular forces affect the boiling point of a substance. Provide an example of two substances with different intermolecular forces and explain why one has a higher boiling point than the other.