Synopsis
Spec references J248: C2.2h J250: C2.2h. Professor Jim Al-Khalili explains how chemical properties are determined by electronic structure using the analogy of a tower block. (If the upper floor is full, any additional electrons added will have to look for an apartment on the next floor up).
History of the Atom: From Rutherford to Bohr | Chemistry: A Volatile History
Spec references J248: C1.2a J250: C1.2a. Professor Jim Al-Khalili explains the history of the atom, its discovery and alternating theories over time. Starting with Rutherford's nuclear model and how this developed into Bohr's model (no mention of Dalton or Thomson). Description of electronic structure using a football pitch analogy. The clip begins to explain chemical reactions.
Discovery of the Neutron | Atom
Spec references J248: C1.2d, C1.2e J250: C1.2d, C1.2e. Professor Jim Al-Khalili explains how James Chadwick discovered the neutron. This solved the mystery of why the masses of the atoms didn't match the number of protons.