1.4 Bulk and surface properties of matter including nanoparticles

Question 1

Nanoscience

Answer 1

Refers to structures that are 1-100nm in size (of the order of a few hundred atoms).

Question 2

Fine particles

Answer 2

• PM_2.5
• Diameters between 100 - 2500 nm

Question 3

Coarse particles

Answer 3

• PM₁₀
• Diameters between 2500-10000 nm
• Referred as dust.

Question 4

Nanoparticles

Answer 4

• Smaller than fine particles.
• High SA:V ratio (as the side of the cube decreases by a factor of 10, the SA:V ratio increases by a factor of 10).
• May have different properties from what they would have in bulk.
• Smaller quantities may be needed to be effective than for materials with normal particle sizes.

Question 5

Uses of nanoparticles

Answer 5

• Computers
• Coatings/construction
• Cosmetics (e.g. sun creams and deodorant)
• Medicine
• Electronics
• Catalysts

Question 6

Disadvantage of nanoparticles

Answer 6

• We don’t know the long term effect of it.