Question

phase changes study guide
name: philanders bowie date:
directions: use your textbook and class notes to complete each section. write neatly in the spaces provided.
part 1: states of matter and particle behavior

1. describe how particle arrangement, distance, and motion differ among solids, liquids, and gases.

a. solids:
b. liquids:
c. gases:

1. explain why temperature is a measure of average kinetic energy.
2. compare the intermolecular forces in solids, liquids, and gases.

part 2: phase change data table
use the correct term for each process and complete the chart. write absorbed or released for the energy column, and describe how particle motion and spacing change.

Explanation:

• Phase Change from Solid → Liquid (Melting): Energy is absorbed. Particles gain energy, break some intermolecular forces, move more freely (vibrate more and can slide past each other), and spacing increases.
• Phase Change from Liquid → Solid (Freezing): Energy is released. Particles lose energy, intermolecular forces become stronger, movement slows down (vibrate in fixed positions), and spacing decreases.
• Phase Change from Liquid → Gas (Vaporization - includes evaporation and boiling): Energy is absorbed. Particles gain enough energy to overcome most intermolecular forces, move rapidly in all directions, and spacing increases significantly.
• Phase Change from Gas → Liquid (Condensation): Energy is released. Particles lose energy, intermolecular forces pull them closer together, movement slows (vibrate and move less freely compared to gas), and spacing decreases.
• Phase Change from Solid → Gas (Sublimation): Energy is absorbed. Particles gain energy directly to overcome intermolecular forces without passing through liquid phase, move freely (like gas particles), and spacing increases.
• Phase Change from Gas → Solid (Deposition): Energy is released. Particles lose energy, intermolecular forces cause them to come together tightly (like solid particles), movement is restricted (vibrate in fixed positions), and spacing decreases.

Answer:

1. Melting; Absorbed; Particles gain energy, move more freely (vibrate more and can slide past each other), spacing increases.
2. Freezing; Released; Particles lose energy, movement slows (vibrate in fixed positions), spacing decreases.
3. Vaporization; Absorbed; Particles gain energy, move rapidly in all directions, spacing increases significantly.
4. Condensation; Released; Particles lose energy, movement slows (vibrate and move less freely compared to gas), spacing decreases.
5. Sublimation; Absorbed; Particles gain energy, move freely (like gas particles), spacing increases.
6. Deposition; Released; Particles lose energy, movement is restricted (vibrate in fixed positions), spacing decreases.