20 - Materials
21 - Elements & Compounds
22 - Solutions
23 - Separating Mixtures
24 - Acids and Bases 1
25 - The Air and Oxygen
26 - Carbon Dioxide
27 - Water
28 - Acids and Bases 2
29 - Atomic Structure
30 - The Periodic Table
31 - Chemical Bonding
32 - Chemical Equations
33 - Metals and Plastics