Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Methanesulfonic Acid

Methanesulfonic Acid is a solid.

CAS 75-75-2 CH4O3S 96.11 g/mol Danger

01 · Identification

What Methanesulfonic Acid is

Methanesulfonic Acid is a solid. Its molecular formula is CH4O3S and its molecular weight is 96.11 g/mol. It melts at 20 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as corrosives.

CAS number75-75-2
EC number200-898-6
Index number607-145-00-4
Molecular formulaCH4O3S
Molecular weight96.11 g/mol
Chemical class Corrosives

Other names for Methanesulfonic Acid

  • methanesulphonic acid

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Methanesulfonic Acid
CodeHazard statement
H314 Causes severe skin burns and eye damage.

Precautionary statements: P260, P280, P301, P310, P331

03 · Physical and chemical properties

Methanesulfonic Acid properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 167 °C (332.6 °F) at 10 mmHg (reduced pressure) HSDB
Melting point 20 °C (68 °F) HSDB
Density 1.4812 g/cm³ at 18 °C HSDB
Solubility Solubility at 26-28 °C in wt %: hexane, 0; benzene, 1.5; methylcyclopentane, 0; toluene, 0.38; o-chlorotoluene, 0.23; ethyl disulfide, 0.47 HSDB
Soluble in alcohol, ether HSDB
Soluble in water HSDB
Vapor pressure 0.000428 mmHg at 25 °C HSDB
0.000428 mmHg Haz-Map
Flash point 189 °C (372.2 °F) HSDB
110 °C (230 °F) Haz-Map
Autoignition temperature 500 °C (932 °F) above this value, at 1013 mmHg HSDB
Lower explosive limit (LEL) 11.4 % by volume by volume HSDB
Electrolysis of a mixture produced oxygen difluoride which exploded. of hydrogen fluoride and methanesulfonic acid HSDB
Upper explosive limit (UEL) 24.3 % by volume by volume HSDB
Corrosivity Corrosive to iron, steel, brass, copper, lead HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Methanesulfonic Acid

Storage conditions

Store in cool place. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Recommended storage temperature: 2 - 8 °C. Heat sensitive.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Materials to avoid: Amines, strong reducing agents, strong oxidizing agents, bases

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check Methanesulfonic Acid in the storage compatibility matrix →

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