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Atoms and Molecules

Atoms Molecules Ions Chemical Equations On-line practice



By the end of this unit, you should be able to :

  1. define atoms
  2. use models, diagrams or symbols to represent atoms
  3. define molecules
  4. state the difference between atoms and molecules
  5. state the differences between molecules of elements and molecules of compounds
  6. state the number and types of atoms, given the chemical formula of a compound
  7. write simple electronic structure of an atom
  8. define valence electrons
  9. define isotopes
  10. define ions and how it is formed (positive and negative ions)
  11. indicate how compounds are formed
  12. briefly explain the formation of ionic compound and covalent compound