CAS No.: 1758-73-2  
Molecular formula : H2NC(=NH)SO2H
Molar mass : 108.11 
Melting Point : 126 C decompose
Specific gravity : 1.68
Solubility (in water) : soluble
Dangerous Goods Class: 4.2 ,UN No: 3341 
Appearance: white crystal powder  
Application : high reduction agent in textile wash and de-color process , bleaching agent, plastic stabilizer, anti-oxidants for organic synthesis
Specification :
Purity : 99.0% min 
Thiourea : 0.1% max
Sulfur(as SO4) :0.2% max
Moisture : 0.1% max
Fe : 0.003% max
Loss after heated : 0.40% max
Ash Content : 0.10% max 
Insoluble In water : 0.02% max
P H : 4.0 at 10 g/l
Stability : decompose on exposure to light and heated 
Packing : 50kgs fibre drum