IB Chemistry - Stoichiometry

IB Chemistry home > Syllabus 2025 > Stoichiometry > The aqueous state

Some solids can mix so intimately with water (or other liquids) that they seem to have disappeared. This process is called dissolution. The liquid phase is called the solvent and the solid phase that dissolves is termed the solute.

The majority of solutions are aqueous, i.e. they involve water as the solvent phase. This is usually indicated by the state symbol (aq) appearing as a subscript after the compound name or formula.

Syllabus reference

Structure 1.4.5 - The molar concentration is determined by the amount of solute and the volume of solution.

  • Solve problems involving the molar concentration, amount of solute and volume of solution.


  • The use of square brackets to represent molar concentration is required.
  • Units of concentration should include g dm–3 and mol dm–3 and conversion between these.
  • The relationship n = CV is given in the data booklet.

Tools and links

  • Tool 1 - What are the considerations in the choice of glassware used in preparing a standard solution and a serial dilution?
  • Tool 1, Inquiry 2 - How can a calibration curve be used to determine the concentration of a solution?

In Chapter 3.5