Sub-topic #1: Molarity and Formality

• Both expresses concentration as moles of solute per

  liter of solution.
• Molarity – concentration of a particular chemical

  species in solution.
• Formality – substance’s total concentration in

  solution without regard to its specific chemical form.
• There is no difference between a substance’s molarity and formality if it dissolves without dissociating into ions.
• Example: The molar concentration of a solution of

  glucose is the same as its formality.
• For substances that ionize in solution, molarity and

  formality are different.
• Example: Dissolving 0.1 mol of Na+ and 0.1 mol of

  Cl-, the molarity of NaCl is zero since there is no

  undissociated NaCl in solution.