Among the following oxoacids, the correct decreasing order of acid strength is (IIT-JEE Advanced, 2014)
The correct option is BHClO4>HClO3>HClO2>HOCl i. Decreasing acid strength is due to the decrease in oxidation state of central atom, e.g. +7 +5 +3 +1 HClO4>HClO3>HClO2>HOCl ii. Decreasing acid strength is also due to the decrease in number of resonating structures of their conjugate base, e.g. HClO4+H2O→H3O⊕+ClO⊖4
Other three conjugate base, e.g., ClO⊖3,ClO⊖2andClO⊖ show 3, 2 and 1 resonating structures.