IB Chemistry - Oxidation

IB Chemistry home > Syllabus 2025 > Redox processes > Reactivity series

Reactivity means how easily substances undergo chemical reaction, and 'relative' means when compared to another substance.

In chapter 9.3, the concept of 'relative reactivity'; the chemical behaviour when compared with other similar substances is discussed.

Syllabus reference

Reactivity 3.2.3 - The relative ease of oxidation and reduction of an element in a group can be predicted from its position in the periodic table.

  • The reactions between metals and aqueous metal ions demonstrate the relative ease of oxidation of different metals.
  • Predict the relative ease of oxidation of metals.
  • Predict the relative ease of reduction of halogens.
  • Interpret data regarding metal and metal ion reactions.


  • The relative reactivity of metals observed in metal/ metal ion displacement reactions does not need to be learned; appropriate data will be supplied in examination questions.

Tools and links

  • Structure 3.1 - Why does metal reactivity increase, and non-metal reactivity decrease, down the main groups of the periodic table?
  • Tool 1, Inquiry 2 - What observations can be made when metals are mixed with aqueous metal ions, and solutions of halogens are mixed with aqueous halide ions?

In Chapter 9.3