4.2.4 Nanoparticles

Question 1

nano particles

Answer 1

1-100nm sized particles

have high SA:V ratio

Question 2

fine particles

Answer 2

100-2500nm

Question 3

coarse particles

Answer 3

2500-10000nm

Question 4

uses of nano particles

Answer 4

in medicine—cancer drugs can be delivered to specific locations in the body in gold ‘nanocages’

carbon nanotube particles are used to improve display screens

silver nano particles are used in face creams

in suncreams—nanoparticles are coated in zinc oxide

in deodorants

catalysts—platinum nanoparticles are used in fuel cells to produce hydrogen ions

catalysts—titanium dioxide nanoparticles are used in self cleaning windows

Question 5

nanoparticles in medicine—cancer drugs can be delivered to specific locations in the body in gold ‘nanocages’

Answer 5

ad:
cancerous tumours will be destroyed but not healthy cells

dis:
new technology, may not be trusted

Question 6

nanoparticles
carbon nanotube particles are used to improve display screens

Answer 6

ad:
reduces power consumption and decreases weight and thickness of screens

dis:
nanoparticles can end up in the environment if screens are not disposed of properly—long term effects in environment are not yet known

Question 7

silver nano particles are used in face creams

Answer 7

ad:
face creams containing nanoparticles can give better and deeper coverage of the skin which can hide wrinkles

dis:
long term effects not yet known, nanoparticles could be absorbed into body and enter cells

Question 8

in suncreams—nanoparticles are coated in zinc oxide

Answer 8

ad:
give better skin coverage and absorb UV light more efficiently, colourless

dis:

long term effects not yet known, nanoparticles could be absorbed into body and enter cells

Question 9

nanoparticles in deodorants

Answer 9

ad:
silver nanoparticles are very effective at killing bacteria

dis:

long term effects not yet known, nanoparticles could be absorbed into body and enter cells

Question 10

catalysts—platinum nanoparticles are used in fuel cells to produce hydrogen ions

Answer 10

ad
large sa:vol so cheaper—less platinum needed for same result

dis:
difficult to dispose of and nanoparticles could accumulate in the environment where the long term effects are not yet known
large quantities could cause an explosion if exposed to a spark

Question 11

catalysts—titanium dioxide nanoparticles are used in self cleaning windows

Answer 11

ad
titanium dioxide nanoparticles catalyse the break down of dirt in the presence of UV light

dis:
nanoparticles could build up in the environment in aquatic habitats—long term effects not yet known

Question 12

silver particles

Answer 12

used in socks to kill bacteria as well as in fridges, sprays used to clean operating theatres and wound dressings