Molar mass118.10g/mol (anhydrous)154.14g/mol (dihydrate).

Appearance colorless crystal

Density1.75g/cm3 (dihydrate)

Melting point 64.5°C (dihydrate) decomposes above 80 C.

The solubility in water is about 600g/L (dihydrate).

PKa decomposes at low pH value.

White block or powder, odorless or slightly leek flavor. Soluble in water, slightly soluble in alcohol. Hydrogen sulfide is released by acid separation, and the pH is stable at >: 3. Stable to alkali. It has strong reducibility. Generally sold in the form of dihydrate (chemical formula: NaHSO2 CH2O 2H2O). It usually contains sodium bisulfite and formaldehyde (NaHSO3 CH2O 2H2O).

It releases heat when it is wet. At 80℃, it begins to decompose and release hydrogen sulfide. 1 10 C is completely decomposed, releasing new hydrogen, and the reduction effect is the strongest at this time.

Sodium formaldehyde sulfoxylate can generate sulfoxylate ion (SO2) in situ, which has strong reducibility, so it can be used as a reducing agent in organic synthesis. Aromatic disulfide reacts with halogenated hydrocarbon in the presence of sodium formaldehyde sulfoxylate to obtain aromatic sulfide.

Reacting with elemental selenium and tellurium, a solution containing a compound having a composition of about Na2Se2 and Na2Tex can be obtained.

S- alkylation with benzyl bromide to produce sulfone;

O- alkylation may also occur, in which case the product will be sulfite.

CAS number: 6035-47-8