Skip to Content
Merck
CN

247626

Sulfur dioxide solution

ACS reagent, ≥6%

Synonym(s):

Sulfurous acid, Sulfurous anhydride

Sign In to View Organizational & Contract Pricing.

Select a Size

About This Item

Linear Formula:
H2SO3
CAS Number:
7782-99-2
Molecular Weight:
82.08
NACRES:
NB.24
PubChem Substance ID:
329752746
UNSPSC Code:
12352300
EC Number:
231-973-1
MDL number:
MFCD00011335
Assay:
≥6% SO2 basis (by Na2S2O3, titration)
Concentration:
≥6%
Form:
liquid
Grade:
ACS reagent

Key Documents

View All Documentation
Technical Service
Need help? Our team of experienced scientists is here for you.
Let Us Assist
Technical Service
Need help? Our team of experienced scientists is here for you.
Let Us Assist

InChI key

LSNNMFCWUKXFEE-UHFFFAOYSA-N

InChI

1S/H2O3S/c1-4(2)3/h(H2,1,2,3)

SMILES string

OS(O)=O

grade

ACS reagent

vapor density

2.3 (vs air)

assay

≥6% SO2 basis (by Na2S2O3, titration)

form

liquid

concentration

≥6%

ign. residue

≤0.005%

density

1.03 g/mL at 25 °C (lit.)

anion traces

chloride (Cl-): ≤5 ppm

cation traces

Fe: ≤5 ppm, heavy metals (as Pb): ≤2 ppm

Quality Level

200

Looking for similar products? Visit Product Comparison Guide

Related Categories

Application

Sulfurous acid can be used as a reducing agent in chemical synthesis.

General description

Sulfurous acid (H2SO3), a weak diprotic acid, is formed when sulfur dioxide (SO2) dissolves in water. Sulfurous acid is a complex mixture of various hydrates of SO2 and the ions H3O+, S2O52- and HSO3-. The predominant species present in the solution are pH dependent.

pictograms

CorrosionExclamation mark
GHS05,GHS07

signalword

Danger

hcodes

H314,H332

Hazard Classifications

Acute Tox. 4 Inhalation - Eye Dam. 1 - Skin Corr. 1B

Storage Class

8B - Non-combustible corrosive hazardous materials

wgk

WGK 1

flash_point_f

Not applicable

flash_point_c

Not applicable

Choose from one of the most recent versions:

Certificates of Analysis (COA)

Lot/Batch Number
MKCZ9466
MKCT8760
MKCQ0685
MKCK6803
SHBJ4747

Don't see the Right Version?

If you require a particular version, you can look up a specific certificate by the Lot or Batch number.

Search for a COA

Already Own This Product?

Find documentation for the products that you have recently purchased in the Document Library.

Visit the Document Library

The thermodynamic ionization constants of sulfurous acid at 25?1.
Tartar HV and Garretson HH.
Journal of the American Chemical Society, 63(3), 808-816 (1941)
M Kharina et al.
Applied biochemistry and biotechnology, 179(2), 307-320 (2016-01-29)
Sulfurous acid was used for pretreatment of sugar beet pulp (SBP) in order to achieve high efficiency of both extraction of carbohydrates and subsequent enzymatic hydrolysis of the remaining solids. The main advantage of sulfurous acid usage as pretreatment agent
Miquel Pascual et al.
Journal of the science of food and agriculture, 95(15), 3067-3076 (2015-07-16)
Rainfed viticulture, mainly in semi-arid environments, is limited by environmental variability, particularly precipitation and its seasonal distribution, and soil water availability, thus ultimately determining the final quality of grape and wine. Studies on the feasibility of practices such as canopy
Daniela Vullo et al.
Bioorganic & medicinal chemistry letters, 16(12), 3139-3143 (2006-04-20)
An inhibition study of the cytosolic carbonic anhydrase (CA, EC 4.2.1.1) isozyme VII (hCA VII) with anions has been conducted. Cyanate, cyanide, and hydrogensulfite were weak hCA VII inhibitors (K(I)s in the range of 7.3-15.2 mM). Cl- and HCO3- showed
Heng Yu et al.
Bioresource technology, 199, 188-193 (2015-09-06)
This study established a new more neutral magnesium bisulfate pretreatment (MBSP) using magnesium bisulfate as sulfonating agent for improving the enzymatic hydrolysis efficiency of corn stover. Using the MBSP with 5.21% magnesium bisulfate, 170°C and pH 5.2 for 60 min
View All Related Papers

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service