One and the same substance may act simultaneously as an oxidising agent and as a reducing agent with the result that a part of it gets oxidised to a higher state and rest of it is reduced to lower state of oxidation. Such a reaction, in which a substance undergoes simultaneous oxidation and reduction is called disproportionation and the substance is said to disproportionate.
Following are the some examples of disproportionation,
Tips & Tricks
|1. If an element is in its highest possible oxidation state in a compound, it can act as an oxidising agent. for example, KMnO4, K2Cr2O7, HNO3, H2SO4, HClO4 etc.|
|2. If an element is in its lowest oxidation state in a compound, it can act as a reducing agent. For example, H2S, H2C2O4, FeSO4, Na2S2O3, SO2, SnCl2, many metals etc.|
|3. The strength of oxyacids of chlorine decrease in the order. HClO4 > HClO3 > HClO2 >HClO|
|4. If highly electronegative element is in its highest oxidation state in a compound that compound can act as powerful oxidant. For example, KClO4, KClO3, KBrO3, KIO3 etc.|
|5. If an element is in intermediate oxidation state in a compound, it can act as both oxidising & reducing agent. For example, H2O2, H2SO3, HNO3, SO2 etc.|