Bulk/surface properties of matter inc nanoparticles (2.4) (R)

Question 1

What does nanoscience refer to? (diameter of nanoparticles)

Answer 1

structures that are 1–100 nm in size, of the order of a few hundred atoms

Question 2

Nanoparticles are much (…) than fine particles

Answer 2

smaller

Question 3

What is the range of diameters of fine particles (PM_2.5)?

Answer 3

between 100 and 2500 nm (1 x 10^-7 m and 2.5 x 10^-6 m)

Question 4

What is the range of diameters of Coarse particles (PM₁₀)

Answer 4

between 1 x 10^-5 m and 2.5 x 10^-6 m

Question 5

What are coarse particles often referred to as?

Answer 5

dust

Question 6

As the side of cube decreases by a factor of 10, what happens to the surface area to volume ratio of the cube?

Answer 6

increases by a factor of 10

Question 7

Why may nanoparticles have properties different from those for the same materials in bulk?

Answer 7

because of their high surface area to volume ratio, which is decreased when in bulk

Question 8

What may nanoparticles SA:V ratio also mean for its effectivity for materials with normal particle sizes?

Answer 8

smaller quantities are needed

Question 9

6 uses needed

What are the uses of nanoparticles?

Answer 9

• medicine
• electronics
• cosmetics
• sun creams
• deodorants
• as catalysts

Some nanoparticles may be used in electrical circuits because they are small and conduct electricity

Question 10

What is an important area of research in nanoscience?

Answer 10

new applications for nanoparticulate materials

Question 11

2 risks

What are the risks of nanoparticles?

Answer 11

• possible nanoparticles may be absorbed into our body and enter our cells
• long-term effects of this unknown

Question 12

What do the potential risks of nanoparticles mean?

Answer 12

It’s important nanoparticles are studied and used carefully

Question 13

How are nanoparticles useful as suncreams?

Answer 13

• Better coverage
• More protection from the Sun’s ultraviolet rays