Nanoparticles

• What is the size range of nanoparticles?

  1 nm to 100 nm
• Why do nanoparticles have different properties compared to the same substance in bulk?

  Because their surface area to volume ratios are very large
• What is nanoscience?

  • The study of structures between 1 and 100 nanometres (nm) in size.
  • Focuses on the unique properties of nanoparticles.
• What is the diameter of atoms and small molecules?

  0.1 nm
• What is the diameter range of fine particles (PM 2.5)?

  100 to 2,500 nm
• What is the diameter range of coarse particles (PM 10)?

  2,500 to 10,000 nm
• What is the thickness of paper in nanometres?

  100,000 nm
• If a zinc oxide nanoparticle has a diameter of 32 nm, how many times larger is it compared to a zinc atom with a diameter of 0.28 nm?

  About 100 times larger
• What does the symbol ≈ represent in calculations?

  It shows that the answer is approximate
• What is the relationship between particle size and surface area to volume ratio?

  • Smaller particles have a greater surface area to volume ratio.
  • If the length of a side of a cube gets 10 times smaller, the ratio gets 10 times bigger.
• How do you calculate the surface area of a cube-shaped nanoparticle with sides of 10 nm?

  Surface area = 6 × 10 × 10 = 600 nm²
• How do you calculate the volume of a cube-shaped nanoparticle with sides of 10 nm?

  Volume = 10 × 10 × 10 = 1,000 nm³
• What is the surface area to volume ratio of a cube-shaped nanoparticle with sides of 10 nm?

  Surface area to volume ratio = $\frac{600}{1000} =$$0.6$
• How many atoms typically make up nanoparticles?

  A few hundred atoms
• How do the properties of nanoparticulate substances differ from bulk substances?

  They exhibit different physical and chemical properties
• What is an order of magnitude calculation?

  An estimate approximating a number to the nearest power of ten
• What is the definition of surface area?

  The total area of all sides on a 3D shape
• What is the definition of volume?

  The measure of the amount of space a 3D shape occupies