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Grade 10 math · D.2 · Science Calculations: Circuits and Chemistry

Moles and molar mass

Moles = mass ÷ molar mass.

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See worked examples
  1. How many moles are in 80 g of oxygen gas (O₂, 32 g/mol)?

    Answer: 2.5 mol

  2. How many moles are in 29.25 g of table salt (NaCl, 58.5 g/mol)?

    Answer: 0.5 mol

  3. How many moles are in 160 g of oxygen gas (O₂, 32 g/mol)?

    Answer: 5 mol

Tip: Moles = mass ÷ molar mass.

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