Chemistry 1.5 - Properties, structure and bonding

• What are the four types of atom?

  • Monatomic
  • Covalent molecular
  • Covalent network
  • Metallic
• What group of elements are monatomic?

  Noble gases
• What elements are covalent molecular?

  Diatomic elements - IBCFONH
• What are all the covalent molecular elements? (IBCFONH)

  • Iodine
  • Bromine
  • Chlorine
  • Fluorine
  • Oxygen
  • Nitrogen
  • Hydrogen
• What elements are covalent networks?

  silicon
• What elements are metallic?

  Metals
• What does delocalised mean?

  The electrons do not move
• Metallic elements have delocalised electrons
• What are the three compound structures?

  • Ionic lattice
  • Covalent molecular
  • Covalent network
• Ionic bonding occurs between a metal and a non metal
• What are the melting points of ionic lattices?

  High
• Why do ionic compounds have high melting points?

  Strong intermolecular forces
• Covalent occurs between two non metals
• What are the melting points of covalent molecular compounds?

  Low
• Why do covalent molecular compounds have low boiling points?

  Weak intermolecular forces
• What is the only covalent network?

  Silicon dioxide
• What are covalent networks boiling points?

  High
• For an element to conduct it must have delocalised electrons
• What metal is the only non insulator?

  Carbon
• Why do covalent compounds not conduct?

  They have no ions
• Why can ionic compounds not conduct when solid?

  The ions cannot move
• Ionic compounds can conduct when liquid but not when solid
• Summary of compounds structure?

  Ionic lattice -> high melting points, conducts as liquid

  Covalent molecules -> low melting points, does not conduct

  Covalent network -> high melting points, does not conduct

  Metallic -> medium melting points, always conducts