Properties of Solid Solids have a definite shape and a definite volume. Particles of solids are tightly packed, not easily compressible Molecules still move but only vibrate about a fixed position. Intermolecular forces are strong
Melting Point• the temperature where a solid turns into a liquid.• at the melting point, the disruptive vibrations are strong enough to overcome the interactions holding them in a fixed position
Sublimation• process of transformation directly from the solid phase to the gaseous phase without passing through an intermediate liquid phase• endothermic phase transition that occurs at temperatures and pressures below a substances triple point in its phase diagram.
Classification of SolidsCrystalline Solids• a solid material whose constituent atoms, molecules, or ions are arranged in an orderly, repeating pattern extending in all three spatial dimensions.Amorphous Solids• lack an ordered internal structure atoms are randomly arranged
• In a crystal, the particles are arranged in a orderly, repeating, three-dimensional pattern called a crystal lattice• A crystal lattice a three-dimensional form that determines the shape of individual units of crystal.
Types of Crystalline Solids Ionic Solids • made up of positive and negative ions and held together by electrostatic attractions. • characterized by very high melting points and brittleness and are poor conductors in the solid state Examples: Sodium Chloride, Zinc Sulphide, Calcium Fluoride
Molecular Solids• Made up of atoms or molecules held together by London dispersion forces, dipole-dipole forces, or hydrogen bonds.• Characterized by low melting points and flexibilityExamples: sugar, ice(water), dry ice
Atomic (Covalent-Network) Solids• Made up of atoms connected by covalent bonds; the intermolecular forces are covalent bonds as well.• Characterized as being very hard with very high melting points and being poor conductors.Examples: Diamond, quartz, graphite
Metallic Solids• are held together by a high density of shared, delocalized electrons, resulting in metallic bonding.• Characterized by high melting points, can range from soft and malleable to very hard, and are good conductors of electricity.