GCSE Chemistry: Nanoscience and Carbon allotropes

What are nanoparticles?

Particles that have a diameter between 1 nm and 100 nm - these are the smallest particles that contain only a few hundred atoms

What is a nanometer in standard form?

1×10^-9 m

Why are nanoparticles useful?

They can have new properties and high reactivity, so less of a substance is needed for the same purpose

Why do nanoparticle have high reactivity?

They have a large surface area to volume ratio.

What are uses for nanoparticles?

Fuel cells

Drug administration

Clothing

Sun creams

Synthetic skin

Deodorants

Electronics

Which nanoparticles are used in fuel cells?

Platinum (Pt)

Which nanoparticles are used in delivery of drugs?

Gold (Au)

Which nanoparticles are used in sun creams?

Titanium dioxide (TiO2) or Zinc oxide (ZnO)

Which nanoparticles are used in clothing and deodorants?

Silver (Ag)

Why may nanoparticles be harmful?

They are highly reactive and behave differently to bulk substance

Why do diamonds have a high melting point?

Lots of strong covalent bonds need to be broken

Why are diamonds strong?

Each carbon atom is covalently bonded to 4 others in a continuous rigid network

Describe the structure of graphite

Each carbon atom forms three covalent bonds to create layers of hexagons. Each carbon atom also has one delocalised electron.

Why is graphite soft?

The layers are only held together by weak intermolecular forces so they can slide over each other

Why does graphite have a high melting point?

The covalent bonds in the layers require high amounts of energy to break

Why does graphite conduct electricity?

The delocalised electrons are free to move and can carry a charge through the structure

What is graphene?

A single layer of graphite

What are fullerenes?

Family of carbon molecules each with carbon atoms linked in rings to form a hollow sphere or tube.

Why are fullerenes useful in delivery of drugs into cells?

They are hollow so drugs can be carried inside them

Why are fullerenes useful as lubricants?

Their spherical shape allows them to roll over each other

What is the formula for Buckminsterfullerene?

C60

What are carbon nanotubes?

Carbon nanotubes are a group of fullerenes that are shaped into long cylinders, they are made of rings formed from six carbon atoms

What are properties of carbon nanotubes?

Carbon nanotubes have high tensile strength, they are good conductors of heat and electricity