sc26, bulk and surface properties including nanoparticles (paper 2) Flashcards
1
Q
define nanoparticle
A
structures consisting of only a few hundred atoms
2
Q
what is the range of size for a nanoparticle
A
1nm - 100nm
3
Q
why might nanoparticles be dangerous
A
- be breathed in, absorbed through the skin or transported into cells
- take a long time to break down
- attract toxic substances to their surfaces
4
Q
nanoparticles have a very small size, what does this make them useful for?
A
- sunscreen: absorb harmful ultraviolet light but can’t be seen on skin
- lightweight strong materials: carbon nannotubes in tennis rockets
- future drug delivery systems: buckyballs consist of hollow balls of carbon atoms
5
Q
properties of metals
A
- can be polished to a shine
- good conductor
- hard, tough, ductile
6
Q
properties of polymers
A
- can be transparent, translucent or opaque
- poor conductors
- often tough and ductile
7
Q
properties of glass ceramics
A
- transparent
- hard but ductile
- poor conductors
8
Q
in what objects can metals be found in
A
- cars
- bridges
- electrical cables
9
Q
properties of clay ceramics
A
- opaque
- hard but brittle
- poor conductors
10
Q
in what objects can polymers be found in
A
- cars
- bridges
- electrical cables
11
Q
in what objects can glass ceramics be found in
A
- glass windows
- bottles
12
Q
in what objects can clay ceramics be found in
A
- bricks
- chine and porcelain
13
Q
define composite material
A
mixture of two or more metals with contrasting properties, combined to produce a material with improved properties
14
Q
define opaque
A
doesn’t let light through
15
Q
define translucent
A
lets light through but not detailed shapes
