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

Sulfanilic acid

Sulfanilic acid is orthorhombic plates or monoclinic from water.

CAS 121-57-3 C6H7NO3S 173.19 g/mol Warning

01 · Identification

What Sulfanilic acid is

Sulfanilic acid is orthorhombic plates or monoclinic from water. Its molecular formula is C6H7NO3S and its molecular weight is 173.19 g/mol. It melts at 288 °C, is practically insoluble in water.

Under the GHS it carries the signal word Warning.

CAS number121-57-3
EC number204-482-5
Index number612-014-00-X
Molecular formulaC6H7NO3S
Molecular weight173.19 g/mol

Other names for Sulfanilic acid

  • sulphanilic acid
  • 4-aminobenzenesulphonic 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 wordWarning
Hazard statements assigned to Sulfanilic acid
CodeHazard statement
H315 Causes skin irritation.
H319 Causes serious eye irritation.
H317 May cause an allergic skin reaction.

Precautionary statements: P261, P264, P272, P280, P302, P305, P313, P332, P333, P337, P338, P352

03 · Physical and chemical properties

Sulfanilic 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
Melting point 288 °C (550.4 °F) decomposes HSDB
287.78 °C (550 °F) decomposes CAMEO
Density 1.49 g/cm³ ICSC
1.485 g/cm³ at 25 °C HSDB
Solubility Insoluble in ethanol and ether HSDB
Soluble in fuming hydrochloric acid HSDB
Slowly sol in water: about 1% at 20 °C, about 1.45% at 30 °C, about 1.94% at 40 °C at 20 °C HSDB
Vapor pressure 2e-7 mmHg Haz-Map

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

04 · Handling and storage

Storing and handling Sulfanilic acid

Reactivity

4-AMINOBENZENE SULFONIC ACID is an amino acid. Reacts weakly with both acids and bases.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Sulfanilic acid in the storage compatibility matrix →

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