... Sodium metabisulphite1,Molecular formula : Na2S2O52,Molecular weight : 190.103,Appearance : white or light yellow crystalline powder4,Main content :96.5%min 5 ... ,Competitive price, Pass ISO 6,Annuual production:20,000mt Quality standard : ... since the production date. It should be transported by clean car, with covering matter, avoid raining. Net ...