Allotropes of Carbon Flashcards
Allotropes
Substances of the same state and element but different structure
Diamonds properties
In diamond, each carbon atom forms four covalent bonds with other
carbon atoms in a giant covalent structure so they cant conduct electricity due to having no free electron or ion
strong as it has 4 strong covalent bonds per atom also leads to so diamond is very hard(As layers cant slide past each other, has a very high melting point
Graphite properties
In graphite, each carbon atom forms three covalent bonds with three other carbon atoms, forming layers of hexagonal rings which have no covalent bonds between the layers(so can slide and has weak intermolecular bonds between molecules leading to low boiling point.
In graphite, one electron from each carbon atom is delocalised leading it to be able to conduct electricity as it can carry a charge and energy
What is graphene
Graphene consists of a single layer of graphite which is a sheet of carbon atoms covalently bonded forming a continuous hexagonal layer
It is essentially a 2D molecule since it is only one atom thick
It has very unusual properties make it useful in fabricating composite materials and in electronics
Graphene properties
It is extremely strong but also amazingly light(It is very strong due to its unbroken pattern and the strong covalent bonds between the carbon atoms)
It conducts heat and electricity
It is transparent(Graphene absorbs 2.3 percent of the visible light that hits it, which means you can see through it without having to deal with any glare
This gives it the potential to be used for making computer screens of the future
It is flexible( can be twisted, pulled and curved to a certain extent without breaking, which means graphene is bendable and stretchable
Fullerenes meaning
Fullerenes are a group of carbon allotropes which consist of molecules that form hollow tubes or spheres
Why can fullerenes be used to deliver drugs and a catalyst
Fullerenes can be used to trap other molecules by forming around the target molecule and capturing it, making them useful for targeted drug delivery systems
They also have a huge surface area and are useful for trapping catalyst molecules onto their surfaces making them easily accessible to reactants so catalysis can take place
Why can fullerenes be used for tennis rackets and as a lubricant
Fullerenes can be used for tennis racket as it has a low diameter to volume ratio so can add strength without adding to much weight
Some fullerenes are excellent lubricants and are starting to be used in many industrial processes
What is the Buckminster fullerene
The first fullerene to be discovered was Buckminsterfullerene (C60) has a spherical shape
What are nanotubes
Graphene can also be rolled into a cylinder to produce an interesting type of fullerene called a nanotube
Properties of Nanotubes and how does this link to there uses
have high tensile strength and are resistant to breaking or stretching(good for electronics as it has a very high length to diameter ratios so add a lot of strength without to much weight
As in graphene, nanotubes can also conduct electricity which makes them useful in composites and specialised materials, electronics and nanotechnology
