Knowledge Organiser: Nanoparticles
Key Terms
- Nanoparticle: 1-100 nm particle with different properties from bulk
- Surface area to volume ratio: increases as particle size decreases
- Fullerene: hollow carbon cage (C₆₀) — used in drug delivery
- Graphene: single layer of graphite — strong conductor
- Nanotechnology: design and use of nanoscale materials
Must-Know Facts
- 1 nm = 10⁻⁹ m (one billionth of a metre)
- Nanoparticles have high surface area to volume ratio
- More reactive than same material in bulk form
- Uses: sunscreen, catalysts, antimicrobials, drug delivery, electronics
- Safety concerns: effects on human health not fully known
- Fullerenes: hollow carbon molecules, simple molecular structure
Key Equations
- 1 nm = 1 × 10⁻⁹ m
- Nanoparticle size range: 1–100 nm
- As particle size ↓, surface area to volume ratio ↑ → increased reactivity
Common Mistakes
- Confusing nano scale with micro scale: 1 nm = 10⁻⁹ m (nano), not 10⁻⁶ m (micro) — nano is 1000× smaller than micro
- Saying nanoparticles are always beneficial: Safety risks exist — effects on human health and environment are not fully understood; must mention both uses AND risks
- Forgetting why nanoparticles are more reactive: Smaller particles = greater surface area to volume ratio = more surface atoms exposed to reactions
- Treating fullerenes as giant covalent: C₆₀ fullerene is a simple molecular structure — it has weak intermolecular forces and a relatively low melting point
Memory Aid
- Sunscreens — TiO₂ blocks UV invisibly
- Catalysts — high surface area, more efficient
- Antimicrobials — silver nanoparticles kill bacteria
- Remote drug delivery — fullerenes carry drugs to target cells
- Electronics — smaller, faster circuits