Sodium Metabisulfite Molecular Formula: Na2S2O5 Standard : GB1893-1998 IndexStandard valueNa2S2O5 ≥96%Fe≤0.005%Heavy metals(Pb)≤0.001%As≤0.0002%ClarityLittle turbid Characteristic: White crystal powder Package : net weight 25Kg/bag, 50Kg/bag or 1200Kg/bag