P2C26 - Properties of matter + Nanoparticles

Question 1

Whats 1 nm in 1m?

Answer 1

(1nm = 1x10-9m).

Question 2

Nano particles have a high surface area, why is this good?

Answer 2

This means less materials can be used for our desired purpose (e.g. as catalysts or in sun cream) compared to using normal sized particles.

This makes them cheaper and more efficient to use than larger particles.

Question 3

What is a disadvantage of nanoparticles?

Answer 3

Nanoscience is new, there might be cons we don’t know about.
E.g. We don’t know the long-term effect of them on the environment or on human health!

Question 4

What are nanoparticles?

Answer 4

Tiny particles between 1 – 100nm in length.
They are larger than individual atoms

Question 5

Whats a special property of a nano particle?

Answer 5

It can change the properties of a material entirely.

eg. Gold nanoparticles can be efficient catalysts.
(Normal gold is unreactive)

Question 6

What are nano particles used for?

Answer 6

Catalysts
Medicine - Fullerene nanoparticles can be used to deliver drugs to a specific area of the body to target a disease.

Electronics - Carbon nanotubes are used in new computer chips because of their good electrical conductivity.

Cosmetics - Nanoparticles are so small that visible light passes through them, making them transparent.
E.g. white substances, like sun cream, can be made transparent by using nanoparticles.

Deodorants - Nanoparticles can have antimicrobial properties. (Kills bacteria)

Question 7

What are ceramics?

Answer 7

Inorganic (not carbon-based), non-metallic solids.

Question 8

What are some examples of ceramics?

Answer 8

Pottery and bricks
Glass

Question 9

What are 2 types of polymers?

Answer 9

Thermosoftening polymers
Thermosetting polymers

Question 10

What are thermosoftening polymers made from?

Answer 10

Monomers that don’t allow cross-links to form between chains

Question 11

What are thermosetting polymers made from?

Answer 11

Monomers that allow cross-links to form between chains

Question 12

What are the conditions to produce low density polyethene?

Answer 12

Moderate temps
High pressure
Catalyst

Question 12

What are features of thermosetting polymers?

Answer 12

Rigid
Hard
Strong
Don’t soften when heated

Question 13

How are composites made?

Answer 13

Embedding a material known as the reinforcement (fibres or fragments) into the matrix (material that surrounds the reinforcement, acting as a binder).

Question 14

What are some examples of composites?

Answer 14

Fibreglass is a composite:
The matrix is a polymer.
The reinforcement is glass fibres.

Carbon fibre
Matrix = polymer
Rein = carbon fibres/nanotubes

Concrete
Matrix = Cement
Rein = Sand/gravel mixture

Question 15

What are some properties that are considered in materials?

Answer 15

Tensile strength (Stretch)
Thermal conductivity
Hardness
Electrical conductivity
Flexibility