Giant Covalent Structures Flashcards
what is diamond?
diamond is a form of pure carbon arranged into a giant lattice
what are the three features of a diamond lattice?
- every C makes 4 covalent bonds
- tetrahedral shape
- strong, grid-like arrangement
why does diamond sublime at a very high temperature?
- covalent bonds are very strong
- there are lots of bonds in the giant lattice
- lots of energy is required to break all the bonds
why is diamond one of the hardest substances?
- covalent bonds are very strong
- there are lots of bonds in the giant lattice
- lots of energy is required to break all the bonds
what is diamond used for?
cutting
why can diamond not conduct electricity?
- there are no freely moving charged particles
- all the atoms are neutral, and all the electrons are stuck inside an atom or a bond
what is graphite?
graphite is another form of pure carbon arranged into a different giant lattice
what are the four features of a graphite lattice?
- layers of hexagons of C atoms
- every C makes 3 covalent bonds
- weak intermolecular forces between layers
- delocalised electrons inside each layer
why does graphite sublime at a very high temperature?
- covalent bonds are very strong
- there are lots of bonds in the giant lattice
- lots of energy is required to break all the bonds
why is graphite soft and slippery?
- the layers can slide easily
what is graphite used for?
as a solid lubricant
why does graphite conduct electricity?
inside the layers the delocalised electrons can move freely
what is silicon dioxide also known as?
silica
what are four features of a silica lattice?
- every Si makes four covalent bonds
- every O makes two covalent bonds
- tetrahedral shape (like diamond)
- strong, grid like arrangement
why does silicon dioxide have similar properties to diamond?
because of its similar bonding and structure
why is silica less expensive than diamond?
it is much less rare
