Sulfurous acid


Sulfuric(IV) acid (United Kingdom spelling: sulphuric(IV) acid), also known as sulfurous (UK: sulphurous) acid and thionic acid, is the chemical compound with the formula H2SO3. Raman spectra of solutions of sulfur dioxide in water show only signals due to the SO2 molecule and the bisulfite ion, HSO−3. The intensities of the signals are consistent with the following equilibrium: 17O NMR spectroscopy provided evidence that solutions of sulfurous acid and protonated sulfites contain a mixture of isomers, which is in equilibrium: Attempts to concentrate the solutions of sulfurous acid simply reverses the equilibrium, producing sulfur dioxide and water vapor. A clathrate with the formula 4SO2·23H2O has been crystallised. Wikipedia

Emergency Response Guide No. 154

Data from the Hazardous Materials Table

Source: 49 CFR §172 (2018/07)

(3) Hazard Class

8
Corrosive liquids

(4) Identification number Help

UN 1833

(5) Packing Group Help

II

(6) Labels Help

Corrosive liquids (8)

(7) Special Provisions (§172.102) Help

×Note:
Special provisions may be very complex. The extracts are taken from 49 CFR §172.102. Please be careful with the information, as necessary, additional conditions may be applied that are not written here. Please check the original source and report bugs.
B3
IB2
T7
TP2

(8) Packing Authorizations (§173.***) Help

(8A) Exceptions154see 49 CFR §173.154
(8B) Non-bulk202see 49 CFR §173.202
(8C) Bulk242see 49 CFR §173.242

(9) Quantity Limits Help

(9A) Passenger aircraft/rail1 L
(9B) Cargo aircraft only30 L

(10) Vessel stowage Help

(10A) Location
(10B) Other

Segregation Chart for Load, Transport, Storage

In this table a statement is contained for each hazard class whether the loading, transport or storage with other hazard classes is allowed, is not permitted or is restricted. The table is based on U.S.-Code 49 CFR §177.848.

red May not be loaded, transported, or stored together in the same transport vehicle or storage facility.
green Load, transport, storage together is not restricted.
yellow Load, transport, storage together is allowed under restrictions.

Substances with similar name

UN-NumberNameHazard Class
UN 1833Sulfurous acid8