Sulfur oxide refers to many types of sulfur and oxygen containing compounds such as SO, SO2, SO3, S7O2, S6O2, S2O2, etc. ) refers to one or more of the following: * Lower sulfur oxides (S nO, S7O2 and S6O2) * Sulfur monoxide (SO) * Sulfur dioxide (SO2 ) * Sulfur trioxide (SO3 ) * Higher sulfur oxides (SO3 and SO4 and polymeric condensates of them) * Disulfur monoxide (S2O) * Disulfur dioxide (S2O2)