C3: Structure and Bonding

• What are compounds?

  Substances with 2 or more elements combined
• How many types of strong chemical bonds are there?

  Three types
• What are the three types of strong chemical bonds?

  Ionic, covalent, and metallic
• What are the particles in ionic bonds?

  Oppositely charged ions
• In what type of compounds do ionic bonds occur?

  Metals combined with non-metals
• What defines covalent bonding?

  Atoms share pairs of electrons
• Where does covalent bonding occur?

  In most non-metallic elements and compounds
• What is the nature of particles in metallic bonding?

  Atoms share delocalised electrons
• In which materials does metallic bonding occur?

  Metallic elements and alloys
• What happens to electrons in ionic bonding?

  Electrons are transferred from metal to non-metal

  
• What charge do metal atoms acquire in ionic bonding?

  Positively charged ions
• What charge do non-metal atoms acquire in ionic bonding?

  Negatively charged ions
• What is an ion?

  An atom that has lost or gained electrons
• Which groups of elements produce ions with full outer shells?

  Groups 1, 2, 6, and 7
• What does a dot and cross diagram represent?

  Electron transfer in ionic compounds

  
• What is the structure of ionic compounds?

  A giant structure of ions
• How are ionic compounds held together?

  By strong electrostatic forces of attraction
• How does the 3D structure of ionic compounds affect forces?

  Forces act in every direction
• What is covalent bonding?

  Atoms share one or more pairs of electrons
• What are polymers?

  Large covalently bonded molecules
• What are giant covalent structures?

  Many atoms covalently bonded in a lattice
• What types of diagrams can represent covalent substances?

  Dot and cross, ball and stick, 3D diagrams
• What is the arrangement of particles in metallic bonding?

  Positive ions and delocalised electrons in pattern
• What is the delocalised electron system in metals?

  Electrons lost from atoms forming positive ions
• What is the mobility of delocalised electrons in metallic bonding?

  They are free to move through the structure
• Why are metallic bonds strong?

  Delocalised electrons are shared throughout structure
• what is ionic bonding?

  transfer of electrons between metals and non - metals
• what happens when they transfer?

  Metal loses electron(s), non metal gains electron(s)
• what happens during ionic bonding?

  Metal forms positive ion, non metal forms negative ion
• what is metallic bonding?

  Attraction between metal cations and delocalized electrons.
• what is a giant metallic structure?

  Lots of metal atoms bonded together
• what is covalent bonding?

  Shared pair of electrons
• what examples of giant covalent structures?

  • diamond
  • silicon dioxide
  • graphite
  • graphene
• what is an example ionic structure?

  a lattice
• what are properties of ionic compounds?

  • high melting/boiling points
  • Strong electrostatic forces between ions so lots of energy needed to break forces
  • Conduct electricity when molten or aqueous
  • Ions are free to move to carry charge
• what are the properties of covalent compounds?

  • small molecules
  • polymers
  • giant covalent structures
• what are small molecules' properties?

  • do not conduct electricity because no charged particles
  • Weak intermolecular forces
  • Low melting and boiling points
  • Intermolecular forces get stronger as the molecule gets bigger
• what are the properties of polymers?

  • Relatively strong intermolecular forces
  • solids at room temp
• what are the properties of giant covalent structures?

  • Solids at room temp
  • Very high melting points
  • Strong covalent bonds between atoms
  • Bonds must be broken to melt the solid
• what are the properties of metals and alloy?

  • conductors of electricity (Delocalised electrons carry charge)
  • Strong metallic bonding (High melting and boiling points)
  • Atoms arranged in regular layers (Malleable as the layers slide over each other)