C2 Flashcards
What is a nanoparticulate?
A material made from nanoparticles, e.g. graphene.
What sets nanoparticulates and materials made ‘in bulk’ apart?
Materials made ‘in bulk’ are larger than 100nm. Nanoparticulates are materials made from nanoparticles, which are 1nm-100nm in diameter.
How are nanoparticles being used/planned to be used in medicine?
Buckminsterfullernes could deliver drugs such as pharmaceuticals around the body, since the small size allows them to enter directly into cells. This makes it more accurate and effective and could potentially save lives.
How are silver nanoparticles being used?
Silver has antibacterial properties, so infusing surgical masks and wound dressings with silver nanoparticles would kill bacteria and prevent infection.
What are some limitations of nanoparticles?
Not enough research done, so there is a chance of nanoparticles being potentially harmful. Their effect on the environment hasn’t been fully investigated.
Their small size and ability to enter cells directly could be hazardous.
Give some features of nanoparticles.
1 - High SA:V ratio. Means they are good candidates for catalysts in industrial chemical reactions as their high surface area will ensure a fast reaction rate while their low volume means a smaller quantity is needed, making it cheaper and more economical.
2 - Extremely small size makes them useful for cosmetics and sunscreen, as they are able to fully cover the skin and maximise protection.
3 - Small size is also useful in medicines, as it means they are able to enter into cells directly to deliver drugs.
Describe the structure of graphite.
Layers of carbon atoms arranged in hexagonal rings. Each carbon
atom has one outer electron that is not in a covalent bond, making it delocalised.
It is a giant covalent structure.
Describe the structure of graphene.
Giant covalent lattice.
A single layer of graphite - so a single layer of carbon atoms arranged in hexagonal rings, with one elctron per carbon atom not in a covalent bond and thus delocalised.
Only one atom thick.
Give some properties of graphene and the structural reasons as to why this is the case.
1- Extremely high melting and boiling points. This is because graphene has large numbers of covalent bonds that require a lot of energy to break.
2 - Very strong. For the same reason given above.
3 - Good conductors of electricity. The delocalised electron on each carbon atom ensures that there are electrons that are free-moving and thus able to move to carry a charge.
4 - Lightweight. Graphene is a single layer of graphite, which means it is only one atom thick.
Give three uses of bucky balls.
1 - Lubricants in machines to reduce friction and allows parts to run smoothly.
2 - Medicine, used to deliver drugs such as pharmaceuticals directly into cells.
3 - Catalusts to speed up reactions, due to high SA:V ratio
Give some properties of carbon nanotubes.
1 - High tensile strength.
2 - High length to diameter ratio.
3 - Good electrical conductors.
4 - Good heat conductors.
What is the type of bond present between the carbon atoms in buckminsterfullerenes?
Covalent.
What are the two different types of polymer?
Thermosetting and thermosoftening.
Define a polymer.
A molecule composed of a long chain of individual repeating units called monomers.
Describe the structure of monomers.
They are simple molecules. They are composed of a few non-metal atoms joined together by covalent bonds.
What is crosslinking?
When chains of polymers (thermosetting) are joined together by strong covalent bonds. This gives them strong intermolecular forces and makes them difficult to separate, resulting in high melting and boiling points.
What are thermosoftening polymers used in?
Making packaging, toy parts, plastic bottles, etc.
What are thermosetting polymers used in?
They have strong intermolecular forces due to their crosslinks, which makes them resistant to heat as they have high melting points. They are therefore used in kettles, laptop chargers and plugs.
What happens to thermosetting polymers compared to thermosoftening polymers when heated?
Thermosetting polymers char and burn. They do not remould.
Thermosoftening melt and are able to be moulded and cooled to be a different solid shape.
Why is it difficult to depict polymers in dot and cross diagrams?
They are just too large.
