structure and bonding of carbon

structure of diamond

allotropes of carbon

only carbon atom

each carbon atom bonds with 4 other carbons, tetrahedron

covalent bonds are identical and strong

no intermolecular forces

conductivity of diamond

doesn’t conduct electricity - all outer shell electrons are held in the 4 covalent bonds around each carbon atom, no freely moving particles to carry charge

mpt of diamond

very high, very strong bonds between the carbon atoms in giant covalent structures, need a lot of energy to break

properties of diamond

hard and dense

graphite structure

each carbon atom in graphite is able to form 3 covalent bonds, forms layers of hexagons leaving 1 free electron

these migrate along layers conducting electricity

weak intermolecular forces so they slide over each other, soft and slippery

mpt of graphite

giant covalent structure, strong covalent bonds, high mpt

properties of graphite

arranged in layers, slide over each other, allows to be used in pencils and lubricant

graphite use

makes inert electrodes dope electrolysis

important for extraction of metals

graphene structure

one single layer of graphite, a sheet of covalently bonded forming a continuous hexagonal layer

2D

one molecule thick

strength of graphene

very strong due to its unbroken pattern and strong covalent bonds between carbon atoms

conductivity of graphene

delocalised electrons which move along allowing it to conduct electricity

fullerenes

a group of carbon allotropes which consist of molecules that form hollow tubes or spheres

use of fullerenes

traps other molecules by forming around the target molecule and capturing it making them useful for drug delivery systems

buckminsterfullerene

first fullerenes, 60 carbon atoms

carbon nanotubes

graphene is rolled into a cylinder to produce this fullerenes

high tensile strength and resistant to breaking or stretching