Chapter 10, Sections 10.8

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Chapter 10, Sections 10.8 10.9Phase Changes
Phase Diagrams

• Phase Changes
• Vapor Pressure the Clausius-Clapeyron equation
• Heating Curves, melting point boiling point
• Phase Diagrams

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Figure 10.42 Pvap Variation with Temperature
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Example 1

• A 0.195 gram sample of water is injected
• into a 2.55 liter flask at 30.0C. At
• equilibrium, what phase(s) of H2O will be
• present? (i.e. Solid, liquid, gas, or a
• combination of two or more of these?)
• The vapor pressure of water at 30.0C is
• 31.8 mmHg.

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Example 2

• What is the standard enthalpy of
• vaporization for a liquid that has a
• vapor pressure of 641 torr at 85.2C
• and a normal boiling point of 95.6C?

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Figure 10.49 Phase diagram for water
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Figure 10.50 Phase diagram for water thought
experiments
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Figure 10.52 Phase Diagram for CO2