Na2SO3 + Br2 +H2O = Na2SO4 + 2HBr是了。弄清机理。Br2有强氧化性，将亚硫酸根氧化成硫酸根。so3变so4必加氧，从水中获得。剩下的H和Br 结合，生成HBr.呵呵
Na2SO3 + Br2 +H2O = Na2SO4 + 2HBr.
Na2SO3 + Br2 +H2O = Na2SO4 + 2HBr.谢谢
Na2SO3 + Br2 +H2O = Na2SO4 + 2HBr
