Question

When bromine is dissolved in water the equilibrium shown below is established.

State and explain the observation that would be made if aqueous sodium hydroxide was added to the equilibrium mixture.

Answer 1

The yellow colour fades // Decolourisation of the mixture. Adding sodium hydroxide lowers the concentration of H⁺ ions. This makes equilibrium to shift to the right i.e. forward reaction is favoured lowering concentration of yellow Br₂ molecules.