AP Chemistry – Class 10

Dates

• Monday, January 26th

Review AP Problems

• yup – any questions?
• turn them in

New Idea – Phase Diagrams

• Compare these two images
• How are they related?
• How do I use each of them?

Phase Diagram

• isotherm vs isobar
• P / T are external conditions
• P & T needed to determine the phase
• Phase change involves changing P or T or both
• EXAMPLE – ice skating
• EXAMPLE – cooking at high altitude
• melting / freezing = fusion
• boiling / condensation = vaporization
• sublimation = sublimation

Cooling Curve

• flat line = phase change
• length of line = magnitude of DH
• slope of line = magnitude of specific heat capacity
• cooling (or heating curve) is what a horizontal slice looks like on P/T Phase diagram