Melting point :190°C
Density :2.34 g/cm³
vapor density :2.3 (vs air)
storage temp. :Store at +5°C to +30°C.
solubility :H₂O: 0.1 M at 20 °C, clear, colorless
form :Powder/Solid
Specific Gravity :2.3
color :White to slightly yellow
PH :2.5-4.5 (25℃, 0.1M in H2O)
Odor :Odorless
PH Range :3-4.5 at 22.2 g/l at 25 °C
Water Solubility :Soluble in water. Insoluble in ethanol.
Sensitive :Air Sensitive
λmax :267nm(H2O)(lit.)
Decomposition :150°C
Merck :14,7645
EPA Substance Registry System :Disulfurous acid, potassium salt (1:2) (16731-55-8)

Symbol(GHS):
Signal word:	Danger
Hazard statements:	Code Hazard statements Hazard class Category Signal word Pictogram P-Codes H318 Causes serious eye damage Serious eye damage/eye irritation Category 1 Danger P280, P305+P351+P338, P310 H335 May cause respiratory irritation Specific target organ toxicity, single exposure;Respiratory tract irritation Category 3 Warning
Precautionary statements:	P261 Avoid breathing dust/fume/gas/mist/vapours/spray. P271 Use only outdoors or in a well-ventilated area. P280 Wear protective gloves/protective clothing/eye protection/face protection. P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing. P403+P233 Store in a well-ventilated place. Keep container tightly closed.