Bonding, structure and properties

Cards (50)

  • What is ionic bonding?

    When a metal reacts with a non metal
  • What happens in ionic bonding?
    Electrons are transferred from the metal to the non-metal, forming ions
  • In ionic bonding, the metal becomes a positive ion but the non metal becomes a negative ion
  • What is covalent bonding?
    When 2 non metals share a pair of electrons
  • What is the saying for covalent bonding?
    Give to get
  • Ionic compounds can only conduct electricity when molten or dissolved in solution
  • Strong bonds between molecules can be found in ionic bonding
  • In covalent bonding, there are weak bonds between molecules so are easily broken
  • Covalent bonds have a low melting and boiling point
  • How can crystals form?
    When ions in a compound are arranged in a giant ionic structure. Also known as a giant ionic lattice
  • Ionic compounds have high melting and boiling points
  • Ionic compounds cannot conduct electricity because their ions are held firmly in place
  • Covalent bonds do not conduct electricity because there are no free electrons to carry the charge
  • What is an allotrope?
    A different form of the same element.
  • What are examples of allotropes of carbon?
    Diamond, graphite and graphene
  • What are giant covalent structures?
    Lots of atoms joined together by covalent bonds
  • What are properties of giant covalent structures?
    Very high melting points and variable electrical conductivity
  • Diamond is the hardest natural substance due to it's rigid structure
  • Diamond has a high melting and boiling point
  • Diamond is shiny and strong
  • What are some uses of diamond?
    Jewelry and drill tips
  • Each carbon in diamond forms 4 covalent bonds
  • Each carbon in graphite forms 3 covalent bonds
  • The structure of graphite includes hexagonal layers
  • Every carbon in graphite has 1 delocalised electron so it can conduct electricity
  • Graphite is slippery because of the layers in it's structure
  • Graphite is a good conductor of electricity because it's delocalised electrons can carry the electric charge
  • Graphene can be used for making objects bulletproof e.g bulletproof vest
  • Most metals are malleable and ductile
  • What does malleable mean?

    The metal can be bent and shaped without it breaking
  • What does ductile mean?
    Where most metals can be drawn into wires for electric cables
  • Metallic bonds are strong so therefore have high melting and boiling points
  • Metals are good conductors of heat and electricity because their delocalised electrons can move throughout the metal
  • The greater the number of outer electrons a metal has, the higher it's melting and boiling point
  • What is a nano particle?
    A particle of a substance that is 1-100nm in diameter
  • Where is nano-silver used?
    Wound dressings to prevent infection, deodorants to kill bacteria, insides of fridges and socks
  • How are nano particles of titanium dioxide used?
    In sunscreen to block UV rays to prevent sunburn and skin cancer
  • What are the issues with nano-particles?

    Long term effects are unknown, they are so small they can pass through our skin and into our bloodstream, cause damage to environment and animals
  • What are smart materials?
    Materials that have properties which mean that they can change reversibly depending on their environment
  • What is thermochromic pigments?
    Pigments which can change colour reversibly with temperature