How the model of the atom changed

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• 7 sections of explanation, worked examples and diagrams
• 1 practice task with hints and worked answers
• A quiz that marks itself as you go
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Other lessons in this sub-strand

1. Inside the atom
2. Atomic number and mass number
3. The proton: identity of an element
4. The neutron: mass without charge
5. The electron: where chemistry happens
6. Comparing protons, neutrons and electrons
7. Why atoms have no overall charge
8. The nucleus and empty space
9. Writing atoms in nuclear notation
10. Worked calculations of particle numbers
11. Isotopes: same element, different mass
12. Hydrogen, carbon and chlorine isotopes
13. Relative atomic mass as a weighted average
14. Energy levels around the nucleus
15. Filling shells: the 2,8,8,2 rule
16. Electron arrangement of hydrogen to neon
17. Electron arrangement of sodium to calcium
18. How to draw atoms
19. Valence electrons
20. Atoms versus ions
21. How the model of the atom changed
22. Radioactivity: an awareness
23. Building models of atoms
24. Putting the atom together