1. Phase Diagram FEBRUARY 11, 2015

2. SCIENCE STARTER DO THE SCIENCE STARTER TAKE 3 MINUTES YOU ARE SEATED AND SILENT ALSO TAKE OUT YOUR JOURNAL

3. Upcoming assessment First assessment this Friday.

4. AIM Explain, in term of heat of fusion and heat of vaporization, which interval (interval DE or interval BC) has a larger amount of heat added.

5. VOCABULARY Triple point Heat of fusion Heat of vaporization

6. phase Phase depends upon chemical structure and state of matter (solid, liquid, gas) A substance in the same PHASE has the same CHEMICAL composition and properties

7. phase Temperature and pressure determine the phase

8. Phase Diagram

9. Phase diagram 3 regions Substance in each region can not change into a different phase Lines represent the pressure and temperature at which phase transition can occur in equilibrium Critical point – the point at which the liquid and gas phases are indistinguishable

10. Triple Point the temperature and pressure at which the solid, liquid, and vapor phases of a pure substance can coexist in equilibrium.

11. Heat energy Amount of heat energy needed to change the temperature of a system of mass between two temperature q=mCΔT  q = heat energy (J)  m = mass of the substance (g)  C = specific heat capacity (J/g K)  ΔT = change in temperature of the substance

12. Heat of fusion Heat energy needed to change 1 g of a substance from solid to liquid ▫q=mH f  q = heat energy required for a phase change (J)  m = mass of the substance (g)  H f = heat of fusion (J/g)

13. Heat of vaporization Heat energy needed to change 1 g of a substance from liquid to a gas ▫q=mH v  q = heat energy required for a phase change (J)  m = mass of the substance (g)  H v = heat of vaporization (J/g)

15. Heat energy examples What is the amount of heat energy released when 50.0 grams of water is cooled from 20.0˚C to 10.0˚C (Jan 2014 Regent)?

16. Heat of fusion example What is the total amount of heat required to liquefied 1.00 gram of H 2 0 (s) at 0.˚C and 1 atm (atmosphere)?

17. Heat of vaporization example What is the total amount of heat required to vaporize 1.00 gram of H 2 0 (l) at 100.˚C and 1 atm (atmosphere)?

18. AIM PROMPT Explain, in term of heat of fusion and heat of vaporization, which interval (interval DE or interval BC) has a larger amount of heat added. Use the RACE format (A paragraph of at least 3 sentences). Use evidence from class discussion and notes.