Bulk and surface properties of matter including nanoparticles

Structure and Bonding — Summary Area Sizes (Triple)

Coarse particles: 2500–10,000 nm
Fine particles: 100–2500 nm
Nanoparticles: 1–100 nm
Nanoparticles have a very large surface area : volume ratio.

Nanoparticles (TRIPLE ONLY)

Nanoparticles

  • Very small particles: 1–100 nm.

  • Contain only a few hundred atoms.

  • Very large surface area : volume ratio → more reactive.

Uses:

  • Catalysts

  • Drug delivery systems

  • Electronics

  • Antibacterial coatings

  • Sun creams

  • Cosmetics

Risks / Concerns:

  • Not fully understood

  • May be toxic

  • Potential environmental impact

  • Must be thoroughly tested before widespread use

Limitations of models:

  • Dot-and-cross: doesn’t show lattice shape or scale.

  • 2D diagrams: inaccurate distances.

  • Ball-and-stick: bonds shown as sticks (not real), gaps exaggerated.

  • Space-filling: no clear bond angles.