Learning Goals (3 hours)

  • Define the terms relative atomic mass (Ar) and relative molecular mass (Mr).
  • Calculate the mass of one mole of a species from its formula.
  • Solve problems involving the relationship between the amount of substance in moles, mass and molar mass.
  • Distinguish between the terms empirical formula and molecular formula.
  • Determine the empirical formula from the percentage composition or from other experimental data.
  • Determine the molecular formula when given both the empirical formula and experimental data.

Khan Academy Lecture: Molecular and Empirical Formulas
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[ invalid file: molecular formula.mp4 ]
Khan Academy Lecture: Formula from Mass Composition
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