Nanotechnology
Chemistry: AQA GCSE Higher, topic 2.3.18
'Clumps' of Particles
Solid and liquid matter often ‘clump’ together into small particles. Different sized ‘clumps’ have different names. The size of these clumps are typically measured in nanometres (1nm = 1x10−9m).
Sizes of particles
- Nanoparticles are 1 - 100 nm long (10 - 1,000 atoms).
- Fine particles are 100 - 2,500 nm long (1,000 - 25,000 atoms).
- Coarse particles (dust) are 2,500 - 10,000 nm long (25,000 - 100,000 atoms).
Disadvantage of nanoparticles
- Nanoscience is still a very new area of research so there are still possible disadvantages of nanoparticles that we do not know about.
- E.g. We don't know the long-term effect of them on the environment or on human health!
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Properties of nanoparticles
- Nanoparticles have special properties because of their high surface area to volume ratio.
- This allows for smaller quantities of them to be used for a desired purpose compared to using normal sized particles which means that they are cheaper and more efficient to use.
Changing materials' properties
- Using nanoparticles can also change the properties of the material completely.
- E.g. ‘Normal’ gold particles are extremely unreactive, but gold nanoparticles can be very efficient catalysts for many processes.
Test yourself on Nanotechnology
A particle is 75 nm long. What name do we give particles of this size?
Why can a smaller quantity of nanoparticles be used to have the same effect as a larger quantity of normal sized particles?
A particle is 1,800 nm long. What name do we give particles of this size?
A particle is 7,500 nm long. What name do we give particles of this size?
How does making gold into nanoparticles change its reactivity compared with normal sized gold particles?