Chapter 10 – Chapter 10 – States of States of MatterMatter

10.110.1 Nature of GasesNature of Gases10.210.2 Nature of LiquidsNature of Liquids10.310.3 Nature of SolidsNature of Solids10.410.4 Changes of StateChanges of State

10.110.1 The Nature of GasesThe Nature of Gases• Kinetic Theory

– Three Main Components to Kinetic Theory

• Gases are composed of particles.

• Particles move rapidly and randomly.

• All collisions are perfectly elastic.

10.110.1 The Nature of Gases The Nature of Gases (cont.)(cont.)

• Gas Pressure– Force exerted

per surface area.

– Barometers and standard pressure:

• 101.3 kPa• 760 mm Hg• 1 atm• STP

10.110.1 The Nature of Gases The Nature of Gases (cont.)(cont.)

• Kinetic Energy and Kelvin Temperature

10.210.2 The Nature of LiquidsThe Nature of Liquids• A Model for Liquids

– Vaporization vs. Evaporation

– What is happening?

10.210.2 The Nature of Liquids The Nature of Liquids (cont.)(cont.)

• Evaporation (cont.)– Closed containers…

• Vapor pressure– When particles collide with the walls of the container with

enough force to produce a pressure above the liquid.» Rate of evaporation = rate of condensation» “dynamic equilibrium”

- Boiling point (b.p.)• The temperature at which the vapor pressure of the liquid equals the

external pressure.

Chapter 10 AssignmentsChapter 10 Assignments• 10.1-10.2

– CPQ’s pg. 289 #20,21,22,24,26,27,29,33,34,36,38,39,42

10.3 The Nature of Solids10.3 The Nature of Solids• A Model for Solids

– Melting point (m.p.): the temperature at which a solid becomes a liquid.

– Freezing point? Just the opposite…

• Crystal Structure and Unit Cells– Most solid substances are crystalline,

i.e. they have ions, atoms, or molecules arranged in an orderly, repeating, 3-D pattern – a crystal lattice.

10.3 The Nature of Solids (cont.)10.3 The Nature of Solids (cont.)

10.3 The Nature of Solids 10.3 The Nature of Solids (cont.)(cont.)

10.3 The Nature of Solids 10.3 The Nature of Solids (cont.)(cont.)

• Allotropes– Two or more different molecular forms of the

same element in the same physical state.– E.g. Sulfur, At. # 16, At. Mass 32.06

• Amorphous solids– Lack an ordered internal structure, atoms are

randomly arranged.– E.g. Silly PuttyTM ,rubber,plastic, asphalt, glass,

…

10.4 Changes of State10.4 Changes of State• Phase Diagrams

10.4 Changes of State 10.4 Changes of State (cont.)(cont.)

• Sublimation– The change of a substance from a solid

to a vapor without passing through the liquid state.

– e.g., dry ice, air fresheners, iodine crystals, etc.

Chapter 10 AssignmentsChapter 10 Assignments• 10.1-10.2

– CPQ’s pg. 289 #20,21,22,24,26,27,29,33,34,36,38,39,42

• 10.3-10.4– CPQ’s pg. 289

# 43,44,45,46,47