Liquids and Solids - Madison Public Schools
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Transcript Liquids and Solids - Madison Public Schools
Liquids and Solids
Solids
Objectives
1. Explain the properties of solids according to the
KMT.
2. Distinguish between amorphous and crystalline
solids.
3. Define crystal structure and unit cell.
Solids
• Definite shape
• Definite volume
• Intermolecular forces
have a large effect;
particles are held in
fixed positions
Properties of Solids
Definite melting point
• Temperature at which the particles of a solid
overcome intermolecular forces that hold them in
fixed positions
• Freezing points and melting points have the same
values
• Amorphous do not have a definite melting point.
Properties of Solids
High Density
• Particles of solid are packed close together as a result
of low K.E. and high intermolecular forces.
Incompressibility
• Particles cannot be pressed into a smaller volume.
Low Rate of Diffusion
• Result of limited particle movement and limited space
between particles
Crystalline Solids
• Solids in which the
particles are arranged in
an orderly geometric
pattern
• Arrangement of
particles is called a
crystal lattice
• The simplest portion of
the lattice is called the
unit cell
Types of Crystalline Solids
Ionic
• Ionic bonds between anions and cations
Covalent Network
• Covalent bonds between atoms.
• Examples: Diamond (Cx), quartz (SiO2)x,
Metallic
• Metal cations surrounded by a see of electrons
Molecular covalent
• Molecules held together by intermolecular forces
(disperson, dipole-dipole, hydrogen bonding
Types of Crystalline Solids
Amorphous Solids
• Particles are arranged
randomly
• Sometimes referred to
as supercooled liquids
• Examples include glass,
rubber, plastics.