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

Azoxybenzene

Azoxybenzene is pale yellow orthorhombic needles.

CAS 495-48-7 C12H10N2O 198.22 g/mol Warning

01 · Identification

What Azoxybenzene is

Azoxybenzene is pale yellow orthorhombic needles. Its molecular formula is C12H10N2O and its molecular weight is 198.22 g/mol. It melts at 36 °C.

Under the GHS it carries the signal word Warning.

02 · Identifiers

Azoxybenzene identifiers and molecular data

Azoxybenzene CAS number and EC number

CAS number495-48-7
EC number207-802-1
Index number (CLP Annex VI)611-002-00-1

Azoxybenzene molecular formula and molecular weight

Molecular formulaC12H10N2O
Molecular weight198.22 g/mol

03 · GHS classification

Azoxybenzene hazard classification

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

Azoxybenzene pictograms and signal word

Signal wordWarning

Azoxybenzene hazard class and category

GHS hazard classes Azoxybenzene falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Acute toxicity - inhalation GHS chapter 3.1 Category 4 H332 GHS07

Azoxybenzene hazard statements (H-codes)

Hazard statements assigned to Azoxybenzene
CodeHazard statement
H332 Harmful if inhaled.
H302 Harmful if swallowed.

This page lists only the codes assigned to Azoxybenzene. 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 Azoxybenzene

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 Azoxybenzene 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

Azoxybenzene precautionary statements

CLP Annex VI assigns 7 precautionary statements to Azoxybenzene. 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

Azoxybenzene 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 азоксибензен
Spanish español Azoxibenceno
Czech čeština azoxybenzen
Danish dansk azoxybenzen
German Deutsch Azoxybenzol
Estonian eesti asoksübenseen
Greek ελληνικά αζωξυβενζόλιο
English English azoxybenzene
French français azoxybenzène
Croatian hrvatski azoksibenzen
Italian italiano azossibenzene
Latvian latviešu azoksibenzols
Lithuanian lietuvių azoksibenzenas
Hungarian magyar azoxibenzol
Maltese Malti ażossibenżen
Dutch Nederlands azoxybenzeen
Polish polski azoksybenzen tlenek difenylodiazenu
Portuguese português azoxibenzeno
Romanian română azoxibenzen
Slovak slovenčina difenyldiazén-oxid
Slovenian slovenščina azoksibenzen
Finnish suomi atsoksibentseeni
Swedish svenska azoxibensen

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

Azoxybenzene GHS label elements

Everything CLP Annex VI fixes for Azoxybenzene, 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

Azoxybenzene

  • Harmful if inhaled.
  • Harmful if swallowed.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • Do not eat, drink or smoke when using this product.
  • Use only outdoors or in a well-ventilated area.
  • IF SWALLOWED:
  • IF INHALED:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Rinse mouth.

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

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

07 · Health hazards

Azoxybenzene health hazards and exposure limits

Azoxybenzene hazard summary

External application to rabbit eyes scored 1 on a scale of 1-10 (10 being most severe) for degree of injury after 24 hours; Causes icteric skin, methemoglobinemia, swelling of liver and spleen, and atrophy of testis and epididymis in oral studies of rats and mice; Emergency treatment: Methemoglobinemia; [HSDB] Dust mixtures with air may be explosive; A skin and eye irritant; May cause liver and kidney injury; [CAMEO] Causes decrease in cellular immune response in intraperitoneal toxic-dose studies of rats; Causes other GI and liver changes in oral lethal-dose studies of mice; [RTECS] May cause irritation and methemoglobinemia; [Alfa Aesar MSDS]

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

08 · Physical and chemical properties

Azoxybenzene 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.

Azoxybenzene boiling point

Property Value Conditions Source
Boiling point Decomposes (NTP, 1992) decomposes CAMEO

Azoxybenzene melting point

Property Value Conditions Source
Melting point 36 °C (96.8 °F) HSDB
36.11 °C (97 °F) CAMEO

Azoxybenzene density

Property Value Conditions Source
Density 1.159 g/cm³ at 26 °C HSDB
1.159 g/cm³ at 26.11 °C CAMEO

Azoxybenzene solubility

Property Value Conditions Source
Solubility less than 1 mg/mL at 68 °F (NTP, 1992) at 20 °C CAMEO
INSOL IN WATER; SOL IN ALCOHOL & ETHER; 43.5 G DISSOLVE IN 100 G PETROLEUM ETHER @ 15 °C at 15 °C HSDB

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

09 · Fire and explosion

Azoxybenzene fire and explosion behaviour

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Azoxybenzene fire potential

SLIGHTLY DANGEROUS...

Source: Hazardous Substances Data Bank (HSDB)

10 · Handling and storage

Azoxybenzene storage and handling

Azoxybenzene storage conditions

MATERIALS WHICH ARE TOXIC AS STORED OR WHICH CAN DECOMPOSE INTO TOXIC COMPONENTS...SHOULD BE STORED IN A COOL WELL VENTILATED PLACE, OUT OF DIRECT RAYS OF THE SUN, AWAY FROM AREAS OF HIGH FIRE HAZARD, AND SHOULD BE PERIODICALLY INSPECTED... INCOMPATIBLE MATERIALS SHOULD BE ISOLATED...

Source: Hazardous Substances Data Bank (HSDB)

Azoxybenzene reactivity

AZOXYBENZENE is an azo compound. Azo, diazo, azido compounds can detonate. This applies in particular to organic azides that have been sensitized by the addition of metal salts or strong acids. Toxic gases are formed by mixing materials of this class with acids, aldehydes, amides, carbamates, cyanides, inorganic fluorides, halogenated organics, isocyanates, ketones, metals, nitrides, peroxides, phenols, epoxides, acyl halides, and strong oxidizing or reducing agents. Flammable gases are formed by mixing materials in this group with alkali metals. Explosive combination can occur with strong oxidizing agents, metal salts, peroxides, and sulfides.

Source: CAMEO Chemicals

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

11 · Questions

Azoxybenzene — frequently asked questions

What is the CAS number of Azoxybenzene?

The CAS number of Azoxybenzene is 495-48-7. Its EC number is 207-802-1.

What is the chemical formula of Azoxybenzene?

The molecular formula of Azoxybenzene is C12H10N2O and its molecular weight is 198.22 g/mol.

What does a Azoxybenzene label have to show?

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

Is Azoxybenzene flammable?

CLP Annex VI assigns Azoxybenzene 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 Azoxybenzene a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Azoxybenzene. 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 boiling point of Azoxybenzene?

The boiling point reported for Azoxybenzene is Decomposes (NTP, 1992), decomposes (CAMEO).

What is the melting point of Azoxybenzene?

The melting point reported for Azoxybenzene is 36 °C (96.8 °F) (HSDB).

How should Azoxybenzene be stored?

MATERIALS WHICH ARE TOXIC AS STORED OR WHICH CAN DECOMPOSE INTO TOXIC COMPONENTS...SHOULD BE STORED IN A COOL WELL VENTILATED PLACE, OUT OF DIRECT RAYS OF THE SUN, AWAY FROM AREAS OF HIGH FIRE HAZARD, AND SHOULD BE PERIODICALLY INSPECTED... INCOMPATIBLE MATERIALS SHOULD BE ISOLATED... (Hazardous Substances Data Bank (HSDB))

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