Chemistry (AQA, Single Science, Higher) C1: Atomic Structure and the Periodic Table (AQA, Single Science, Higher) 4.1.1 A simple model of the atom, symbols, relative atomic mass, electronic charge and isotopes – Part 2: Mixtures (AQA) Lesson Progress 4.1.1 A simple model of the atom, symbols, relative atomic mass, electronic charge and isotopes – Part 2: Mixtures (AQA) Previous Topic Back to Lesson Next Topic Previous Topic Back to Lesson Next Topic