Bulk and surface properties of matter including nanoparticles (chemistry only)

2.4.1  Sizes of particles and their properties


  • 1-100nm in size, a few hundred atoms thick
  • High SA:vol ratio
  • Smaller than fine particles (PM5) – diameters between 100-2500nm (1×10-7-2.5×10-6m)
  • Coarse particles (PM10) – diameters between 1×10-5-2.5×10-6m – often referred to as dust
  • Why good?

    Stronger, harder, high SA:V ratio, very small – fit in small gaps

  • 2.4.2  Uses of nanoparticles


  • Catalyst for fuel – large SA:V ratio
  • Drug delivery – tiny, absorb easily by body
  • Sun cream – better skin coverage, more effective protection from UV rays


  • Potential cell damage in body
  • Harmful effects on environment
  • Suggest why using nanoparticles is good for environment? (2)
  • Tennis ball last longer (coz keep it hard)
  • Less tennis ball needed to make
  • Less material/energy used, pollution caused, waste

Suggest and explain why use of nanosized catalyst particles reduce cost of catalytic converter. (3)

  • 1-100nm in size
  • Large SA
  • Less catalyst needed