01 · Overview
What is National Chemistry Week?
National Chemistry Week (NCW) has been held annually since 1987, organised by the American Chemical Society (ACS). It runs during the third full week of October and reaches an estimated four million people each year through school visits, public demonstrations, and community events. Each year is themed — recent years have explored chemistry's role in food, materials, health, and the environment.
Outside the USA, the Royal Society of Chemistry, the German Chemical Society (GDCh), and the European Chemical Society (EuChemS) all run equivalent public-engagement programmes. In the UK, the RSC's Chemistry Week activities focus on secondary school audiences; the Chemistry Olympiad (see UK Chemistry Olympiad) provides a competitive strand for strong students.
02 · Activities
Hands-on activities with curriculum connections
ELEPHANT TOOTHPASTE
Catalytic decomposition of H₂O₂ by KI or yeast produces a dramatic foam. Demonstrates reaction rates, catalysis, and activation energy.
RED CABBAGE pH
Anthocyanins in red cabbage change colour across pH 2–12. Test household acids and bases. Demonstrates indicators, pH, and acid–base chemistry.
→ pH · Acids and bases
COPPER ELECTROPLATING
Connect a copper anode and steel cathode in copper sulfate solution. Copper deposits visibly in minutes. Demonstrates electrolysis and redox.
→ Electrochemistry · Ion
FLAME TESTS
Metal chlorides in a flame emit characteristic colours: Li (crimson), Na (yellow), K (lilac), Cu (blue-green). Demonstrates atomic emission spectra.
POLYMER SLIME
PVA glue cross-linked with borax or contact lens solution. Explore how chain length, cross-link density, and water content change properties.
→ Polymer
03 · Topics to explore
Chemistry themes worth exploring this week
NCW is an opportunity to go deeper on topics you find fascinating. Some ideas aligned with current research:
- Green chemistry — designing reactions that minimise waste, use renewable feedstocks, and avoid toxic reagents. Links to microplastics and plastic-eating enzymes.
- Energy materials — perovskite solar cells, solid-state batteries, and green hydrogen catalysis are all fundamentally problems in solid-state and physical chemistry. See perovskite solar cells.
- Electrochemistry — from charging your phone to electrolysing water into hydrogen. See the Electrochemistry guide.
- Thermodynamics and equilibrium — why reactions go in one direction, and what conditions can reverse them. See the Equilibrium glossary entry and the Thermodynamics guide.
National Chemistry Week — common questions
- NCW is held in the third full week of October in the USA, organised by the American Chemical Society (ACS). Each year has a new theme — past themes have included "Explore the Chemistry of Colour", "Chemistry is Out of This World", and "Molecules Matter". The RSC runs comparable UK activities.
- The ACS provides free experiment kits and activity guides. Local sections host hands-on events in schools and community centres. Many universities open their labs. Online, the ACS runs a "Chemists Celebrate Earth Week" companion event in April. For UK events, check the Royal Society of Chemistry calendar.
- Popular activities include elephant toothpaste (reaction rates and catalysis), red cabbage pH indicator, polymer slime, electroplating (electrochemistry), and flame tests (atomic emission spectroscopy). Each one connects directly to curriculum topics.