Character use

Overview

Sodium pyrosulfite, sodium sulfite, oxygen bisulfite, sodium metabisulfate, sodium pyrosfite molecular formula Na2S2O5

Molecular weight 190.10

Appearance and properties: colorless prismatic crystal or white powder; sulfur dioxide flavor, acid, salt; storage time color gradually yellow.

Melting point (℃): > 300 (decomposition)

Relative density (water = 1): 1.48

Solubility: soluble in water, the aqueous solution is acid (54G / 100ml water at 20 ℃; 81.7g/100ml water at 100 ℃). Soluble in glycerin, slightly soluble in ethanol Relative density 1.4. Soluble in water and glycerin, slightly soluble in ethanol. It is easy to decompose when damped and oxidize into sodium sulfate when exposed in air. Contact with strong acid to release sulfur dioxide and generate corresponding salts. Heat to 150 ℃ for decomposition.

Stability and reactivity

Forbidden compound: strong acid, strong oxidant.

Conditions to avoid contact: moist air [2]

Safety terminology

S26In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.

In case of contact with eyes, please wash with plenty of water immediately and ask for doctor's advice.

S39Wear eye / face protection.

Wear goggles or masks.

S46If swallowed, seek medical advice immediately and show this container or label.

If swallowed carelessly, seek medical advice immediately and show the container or label.

Risk terminology

R22Harmful if swallowed.

Harmful if swallowed.

R31Contact with acids liberates toxic gas.

Release toxic gas in case of acid.

R41Risk of serious damage to the eyes.

Serious damage to eyes.