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Valence electrons

Chemistry · Grade 10 · about 40 minutes

The outer-shell electrons are the ones that react; they are the last number in the arrangement.

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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