1. PHASE CHANGES
OF WATER

2. Melting: Solid to Liquid Freezing: Liquid to Solid
Both occur at 0° C

3. Evaporation: Liquid to Gas Condensation: Gas to Liquid
Both occur at 100°C

4. Sublimation: Solid <------> Gas

5. * *Temperature does not change during a phase change.

6. Added heat is converted to potential energy called latent heat.

7. Latent heat: energy needed for every molecule of the substance to change phase.

8. Latent heat of fusion: 334 Joules/gram Latent heat of vaporization: 2260 J/gram

9. Melting : ice absorbs 334 J/gram Freezing : water releases 334 J/gram

10. Vaporization: : water absorbs 2260 J/gram Condensation: water vapor releases 2260 J/g

12. Moisture is added to the atmosphere by:

13. 1. Evaporation from lakes, oceans, etc.

14. 2. Transpiration: water released from plants
Evapotranspiration includes both
Transpiration

15. The rate of evaporation can be increased by:

16. 1. increasing temperature

17. decreasing moisture in the air

18. increasing air circulation (more wind)

19. 4. increasing surface area

20. Specific (absolute) humidity: amount of water vapor by weight in a given volume of air.

21. Humidity is measured with: hygrometer or sling psychrometer

23. The “wet sock” of a psychrometer cools because it loses energy to the evaporating water.