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.

02 · Identifiers

Sulfanilic acid identifiers and molecular data

Sulfanilic acid CAS number and EC number

CAS number121-57-3
EC number204-482-5
Index number (CLP Annex VI)612-014-00-X

Sulfanilic acid molecular formula and molecular weight

Molecular formulaC6H7NO3S
Molecular weight173.19 g/mol

Other names for Sulfanilic acid

  • sulphanilic acid
  • 4-aminobenzenesulphonic acid

03 · GHS classification

Sulfanilic acid hazard classification

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

Sulfanilic acid pictograms and signal word

Signal wordWarning

Sulfanilic acid hazard class and category

GHS hazard classes Sulfanilic acid falls into
Hazard class Category From code Pictogram
Skin corrosion/irritation GHS chapter 3.2 Category 2 H315 GHS07
Serious eye damage/eye irritation GHS chapter 3.3 Category 2A H319 GHS07
Skin sensitisation GHS chapter 3.4 Category 1 or 1A or 1B H317 GHS07

Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.

Sulfanilic acid hazard statements (H-codes)

Hazard statements assigned to Sulfanilic acid
CodeHazard statement
H315 Causes skin irritation.
H319 Causes serious eye irritation.
H317 May cause an allergic skin reaction.

This page lists only the codes assigned to Sulfanilic acid. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for Sulfanilic acid

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Sulfanilic acid issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

Sulfanilic acid precautionary statements

CLP Annex VI assigns 12 precautionary statements to Sulfanilic acid. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

Sulfanilic acid name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български сулфанилова киселина 4-аминобензенсулфонова киселина
Spanish español Ácido sulfanílico ácido 4-aminobencenosulfónico
Czech čeština sulfanilová kyselina 4-aminobenzensulfonová kyselina
Danish dansk sulfanilsyre 4-aminobenzensulfonsyre
German Deutsch Sulfanilsäure 4-Aminobenzolsulfonsäure
Estonian eesti sulfaniilhape 4-aminobenseensulfoonhape
Greek ελληνικά σουλφανιλικό οξύ 4-αμινοβενζολοσουλφονικό οξύ
English English sulphanilic acid 4-aminobenzenesulphonic acid
French français acide sulfanilique acide 4-aminobenzènesulfonique
Croatian hrvatski sulfanilna kiselina 4-aminobenzensulfonska kiselina
Italian italiano acido solfanilico 4-aminobenzensolfonico
Latvian latviešu sulfanilskābe 4-aminobenzolsulfonskābe
Lithuanian lietuvių sulfanilo rūgštis 4-aminobenzensulfonrūgštis
Hungarian magyar szulfanilsav 4-aminobenzolszulfonsav
Maltese Malti aċidu sulfaniliku aċidu 4-amminobenżensulfoniku
Dutch Nederlands sulfanilzuur 4-aminobenzeensulfonzuur
Polish polski kwas sulfanilowy kwas 4-aminobenzenosulfonowy
Portuguese português ácido sulfanílico ácido 4-aminobenzenossulfónico
Romanian română acid sulfanilic acid 4-aminobenzensulfonic
Slovak slovenčina kyselina sulfanilová kyselina 4-aminobenzénsulfónová
Slovenian slovenščina sulfanilna kislina 4-aminobenzensulfonska kislina
Finnish suomi sulfaniilihappo 4-aminobentseenisulfonihappo
Swedish svenska sulfanilsyra 4-aminobensensulfonsyra

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

Sulfanilic acid GHS label elements

Everything CLP Annex VI fixes for Sulfanilic acid, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS07 Exclamation mark pictogram

Warning

Sulfanilic acid

  • Causes skin irritation.
  • Causes serious eye irritation.
  • May cause an allergic skin reaction.
  • Avoid breathing dust/fume/gas/mist/vapours/spray.
  • Wash thoroughly after handling.
  • Contaminated work clothing should not be allowed out of the workplace.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF ON SKIN:
  • IF IN EYES:
  • Get medical advice/attention.
  • If skin irritation occurs:
  • If skin irritation or rash occurs:
  • If eye irritation persists:
  • Remove contact lenses, if present and easy to do. Continue rinsing.
  • Wash with plenty of water/

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Sulfanilic acid in the GHS label constructor →

07 · Health hazards

Sulfanilic acid health hazards and exposure limits

Sulfanilic acid hazard summary

An eye and mild skin irritant; May cause skin sensitization; In monohydrate form at room temperature; Becomes anhydrous near 100 deg C; [ICSC] Sensitizing in 5 of 6 guinea pig and 1 of 2 mouse skin tests; [IUCLID] Emergency medical treatment: irritants; [HSDB] May cause skin, eye, and mucous membrane irritation; [CAMEO] An irritant; [MSDSonline]

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

08 · 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.

Sulfanilic acid melting point

Property Value Conditions Source
Melting point 288 °C (550.4 °F) decomposes HSDB
287.78 °C (550 °F) decomposes CAMEO

Sulfanilic acid density

Property Value Conditions Source
Density 1.49 g/cm³ ICSC
1.485 g/cm³ at 25 °C HSDB

Sulfanilic acid solubility

Property Value Conditions Source
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

Sulfanilic acid vapor pressure

Property Value Conditions Source
Vapor pressure 2e-7 mmHg Haz-Map

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

09 · Handling and storage

Sulfanilic acid storage and handling

Sulfanilic acid safe storage

Separated from strong acids and strong bases.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

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 →

10 · Questions

Sulfanilic acid — frequently asked questions

What is the CAS number of Sulfanilic acid?

The CAS number of Sulfanilic acid is 121-57-3. Its EC number is 204-482-5.

What is the chemical formula of Sulfanilic acid?

The molecular formula of Sulfanilic acid is C6H7NO3S and its molecular weight is 173.19 g/mol.

What does a Sulfanilic acid label have to show?

Under CLP Annex VI the label for Sulfanilic acid carries the pictogram Exclamation mark and the signal word is Warning.

Is Sulfanilic acid flammable?

CLP Annex VI assigns Sulfanilic acid no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it.

Is Sulfanilic acid a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Sulfanilic acid. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.

What is the melting point of Sulfanilic acid?

The melting point reported for Sulfanilic acid is 288 °C (550.4 °F), decomposes (HSDB).

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