Structure and Properties of Solids Flashcards
4 main categories solids can be classified into
- Ionic solids
- Metallic solids
- Covalent molecular solids
- Covalent network solids
Crystalline solids
Regular arrangement of atoms, ions, or molecules
Amorphous Solids
No regular arrangement
Ionic solids
- forms from metal and non-metal
- in crystal lattice structure
- alternating cations and anions
Ionic solids physical properties
- Hard and brittle solid
- Dissolves in water
- Conducts electricity in solution
- high melting point
How are metallic solids formed?
By closely packed atoms held together by electrostatic interactions and free floating electrons
What is the electron sea theory?
- Positively charged nuclei remain fixed
- Electrons can flow between nuclei
What does electron sea theory explain?
The low ionization energy of metals
Properties of metallic solids
- Shiny/has lustre
- Malleable
- Electrical conductors
- Hard and strong
Covalent Molecular Solid properties
- Low melting points
- Little hardness
- Electrical non-conductor (cuz its composed of neutral atoms)
Covalent Network Structures
Bonds between atoms form an interwoven network
What is an allotrope?
Different structures with the same element
4 allotropes of carbon
- Graphite
- Diamond
- Buckyball
- Carbon Nanotubes
Graphite properties
- Slippery
- Black
- Good conductors
- Hexagonal shape sheets
Diamond Properties
- Extreme hardness
- very high melting point
- Not good conductors of electricity