IB Chemistry - Acids and Bases

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Hydrolysis: 'hydro' = water; 'lysis' = break apart. Literally, breaking apart in water.

Syllabus reference

Reactivity 3.1.12 - The pH of a salt solution depends on the relative strengths of the parent acid and base. (HL)

  • Construct equations for the hydrolysis of ions in a salt, and predict the effect of each ion on the pH of the salt solution.


  • Examples should include the ammonium ion NH4+, the carboxylate ion RCOO–, the carbonate ion CO32–, and the hydrogencarbonate ion HCO3.
  • The acidity of hydrated transition element ions and Al3+(aq) is not required.

Tools and links

In Chapter 8.7