Simran Vinaik
Last Activity: 5 Years ago
1. In an intermolecular redox reaction, oxidation-reduction takes place when molecules of two different substances react with each other.
e.g. The reaction between chlorine and hydrogen sulphide :
Cl2 + H2S = 2HCl + S
Here chlorine is reduced from zero oxidation state to -1 state, and sulphur is oxidised from -1 to zero oxidation state.
Most of the redox reactions are intermolecular in nature.
2. In intramolecular redox reaction, the molecule of a single substance undergoes oxidation-reaction by the process decomposition.
e.g. Thermal decomposition of ammonium nitrite into N2 and H2O :
NH4NO2 = N2 + 2H2O
Here, the oxidation number of nitrogen in NH4+ ion changes from -3 to zero (oxidation), and that of nitrogen in NO2- ion changes from +3 to zero (reduction) in the formation of N2.