Disproportionation Reactions (Edexcel IAL Chemistry)

Disproportionation

Spec point — 8.7

Disproportionation reactions

• A disproportionation reaction is a reaction in which the same species is simultaneously oxidised and reduced

Example of a disproportion reaction in which the same species (chlorine in this case) has been both oxidised and reduced

Worked Example Balancing disproportionation reactions

Balance the disproportionation reaction which takes place when chlorine is added to hot concentrated aqueous sodium hydroxideThe products are Cl^- and ClO₃^- ions and water

Answer

Step 1: Write the unbalanced equation and identify the atoms that change in oxidation number:

Step 2: Deduce the oxidation number changes:

Step 3: Balance the oxidation number changes:

Step 4: Balance the charges

Step 5: Balance the atoms