The formula for peroxodisulphuric acid is H2S2O8. It has Two S-OH, Four S=O, One S-O-O-S bonds. Sulphuric acid formula is H2SO4. It has Two S-OH, Two S=O bonds. Pyrosulphuric acid has formula H2S2O7 it has two S-OH, four S=O, One S-O-S. Sulphurous acid has formula H2S2O3 and it has two S-OH, one S=O bonds. The structures of the given compounds are given below.
