435597

Sulfuric acid, fuming

reagent grade, 20%, as free SO₃

• Synonym(s): Oleum
• Linear Formula: H₂SO₄ · (SO₃)_x
• CAS Number: 8014-95-7
• Molecular Weight: 98.08
• Beilstein/REAXYS Number: 2037554
• MDL number: MFCD00137792
• UNSPSC Code: 12352106
• PubChem Substance ID: 329756351
• NACRES: NA.21

Properties

• grade: reagent grade
• Quality Level: 100
• vapor density: 3 (vs air)
• vapor pressure: 2 mmHg ( 25 °C)
• form: liquid
• concentration: 20% (free SO₃)
• density: 1.925 g/mL at 25 °C (lit.)
• SMILES string: O=S(=O)=O.OS(O)(=O)=O
• InChI: 1S/H2O4S.O3S/c1-5(2,3)4;1-4(2)3/h(H2,1,2,3,4);
• InChI key: HIFJUMGIHIZEPX-UHFFFAOYSA-N

Description

General description

Fuming sulfuric acid is an inorganic acid, that can be produced by the addition of sulfur trioxide to concentrated sulfuric acid. It is commonly used as a sulfonating reagent in sulfonation reactions. When fuming sulfuric acid is employed as reaction medium, bromination takes place only in the pyridine nucleus of isomeric methylpyridines and 2,6-dimethylpyridine. It can also oxidize fullerene C₆₀ to form fullerene polymers.

Application

Fuming sulfuric acid may be used as a sulfonating agent for the synthesis of:

• sulfonated poly(1,4-phenylene sulfide)
• water-soluble polyphosphazene polyelectrolyte
• sulfated graphene

Safety Information

• pictograms: GHS06,GHS05
• signalword: Danger
• hcodes: H314,H330,H335
• pcodes: P260 - P271 - P280 - P303 + P361 + P353 - P304 + P340 + P310 - P305 + P351 + P338
• Hazard Classifications: Acute Tox. 2 Inhalation - Skin Corr. 1A - STOT SE 3
• target_organs: Respiratory system
• supp_hazards: EUH014
• Storage Class: 6.1A - Combustible acute toxic Cat. 1 and 2 / very toxic hazardous materials
• wgk_germany: WGK 1
• flash_point_f: Not applicable
• flash_point_c: Not applicable