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

4-Nitrosophenol

4-Nitrosophenol is pale yellow orthorhombic needles, browns @ 126 °c.

CAS 104-91-6 C6H5NO2 123.11 g/mol Danger

01 · Identification

What 4-Nitrosophenol is

4-Nitrosophenol is pale yellow orthorhombic needles, browns @ 126 °c. Its molecular formula is C6H5NO2 and its molecular weight is 123.11 g/mol. It melts at 138 °C.

Under the GHS it carries the signal word Danger.

02 · Identifiers

4-Nitrosophenol identifiers and molecular data

4-Nitrosophenol CAS number and EC number

CAS number104-91-6
EC number203-251-6
Index number (CLP Annex VI)604-042-00-6

4-Nitrosophenol molecular formula and molecular weight

Molecular formulaC6H5NO2
Molecular weight123.11 g/mol

03 · GHS classification

4-Nitrosophenol hazard classification

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

4-Nitrosophenol pictograms and signal word

Signal wordDanger

4-Nitrosophenol hazard class and category

GHS hazard classes 4-Nitrosophenol falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Serious eye damage/eye irritation GHS chapter 3.3 Category 1 H318 GHS05
Germ cell mutagenicity GHS chapter 3.5 Category 2 H341 GHS08
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 2 H411 GHS09

4-Nitrosophenol hazard statements (H-codes)

Hazard statements assigned to 4-Nitrosophenol
CodeHazard statement
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H302 Harmful if swallowed.
H318 Causes serious eye damage.
H411 Toxic to aquatic life with long lasting effects.

This page lists only the codes assigned to 4-Nitrosophenol. 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 4-Nitrosophenol

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 4-Nitrosophenol 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

4-Nitrosophenol precautionary statements

CLP Annex VI assigns 14 precautionary statements to 4-Nitrosophenol. 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.

Disposal

What has to happen to the contents and the empty container.

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

4-Nitrosophenol 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 4-нитрозофенол
Spanish español 4-Nitrosofenol
Czech čeština 4-nitrosofenol
Danish dansk 4-nitrosophenol
German Deutsch 4-Nitrosophenol
Estonian eesti 4-nitrosofenool
Greek ελληνικά 4-νιτρωδοφαινόλη
English English 4-nitrosophenol
French français 4-nitrosophénol
Croatian hrvatski 4-nitrozofenol
Italian italiano 4-nitrosofenolo
Latvian latviešu 4-nitrozofenols
Lithuanian lietuvių 4-nitrozofenolis
Hungarian magyar 4-nitrozofenol
Maltese Malti 4-nitrosofenol
Dutch Nederlands 4-nitrosofenol
Polish polski 4-nitrozofenol
Portuguese português 4-nitrosofenol
Romanian română 4-nitrozofenol
Slovak slovenčina 4-nitrózofenol
Slovenian slovenščina 4-nitrozofenol
Finnish suomi 4-nitrosofenoli
Swedish svenska 4-nitrosofenol

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

4-Nitrosophenol GHS label elements

Everything CLP Annex VI fixes for 4-Nitrosophenol, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS08 Health hazard pictogramGHS05 Corrosion pictogramGHS07 Exclamation mark pictogramGHS09 Environment pictogram

Danger

4-Nitrosophenol

  • Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Harmful if swallowed.
  • Causes serious eye damage.
  • Toxic to aquatic life with long lasting effects.
  • Obtain special instructions before use.
  • Do not eat, drink or smoke when using this product.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF IN EYES:
  • IF exposed or concerned:
  • Immediately call a POISON CENTER/doctor/
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Get medical advice/attention.
  • Rinse mouth.
  • Remove contact lenses, if present and easy to do. Continue rinsing.
  • Collect spillage.
  • Dispose of contents/container to

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

Need this as an actual label? Open 4-Nitrosophenol in the GHS label constructor →

07 · Physical and chemical properties

4-Nitrosophenol 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.

4-Nitrosophenol melting point

Property Value Conditions Source
Melting point 138.06 °C (280.5 °F) range, midpoint shown CAMEO

4-Nitrosophenol solubility

Property Value Conditions Source
Solubility MODERATELY SOL IN WATER; SOL IN DILUTE ALKALIES GIVING GREEN TO BROWNISH GREEN SOLUTIONS; SOL IN ALC, ETHER, ACETONE HSDB
SOL IN HOT BENZENE HSDB
less than 1 mg/mL at 70 °F (NTP, 1992) at 21.11 °C CAMEO

4-Nitrosophenol vapor pressure

Property Value Conditions Source
Vapor pressure 0.15 mmHg Haz-Map

4-Nitrosophenol lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) EXPLODES ON CONTACT WITH CONCN ACID, ALKALI, OR FIRE. A TECHNICAL GRADE EXPLODED ON STORAGE. HSDB
DANGEROUS...EXPLOSION RISK...MAY EXPLODE SPONTANEOUSLY. HSDB
NITROSOPHENOL EXPLODES ON HEATING... HSDB

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

08 · Fire and explosion

4-Nitrosophenol 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.

4-Nitrosophenol fire potential

STORED BARRELS HEATED SPONTANEOUSLY & CAUSED A FIRE. CONTAMINATION OF THE BULK MATERIAL BY ACID OR ALKALI MAY CAUSE IGNITION. THE TENDENCY TO SPONTANEOUS IGNITION WAS FOUND TO BE ASSOCIATED WITH THE PRESENCE OF NITRATES IN SODIUM NITRITE USED IN PREPARATION.

Source: Hazardous Substances Data Bank (HSDB)

09 · Handling and storage

4-Nitrosophenol storage and handling

4-Nitrosophenol reactivity

P-BENZOQUINONE MONOXIME explodes when heated. Explodes on contact with acid, alkali (NTP, 1992).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 4-Nitrosophenol in the storage compatibility matrix →

10 · Questions

4-Nitrosophenol — frequently asked questions

What is the CAS number of 4-Nitrosophenol?

The CAS number of 4-Nitrosophenol is 104-91-6. Its EC number is 203-251-6.

What is the chemical formula of 4-Nitrosophenol?

The molecular formula of 4-Nitrosophenol is C6H5NO2 and its molecular weight is 123.11 g/mol.

What does a 4-Nitrosophenol label have to show?

Under CLP Annex VI the label for 4-Nitrosophenol carries the pictograms Health hazard, Corrosion, Exclamation mark and Environment and the signal word is Danger.

Is 4-Nitrosophenol flammable?

CLP Annex VI assigns 4-Nitrosophenol 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 4-Nitrosophenol a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for 4-Nitrosophenol. 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 4-Nitrosophenol?

The melting point reported for 4-Nitrosophenol is 138.06 °C (280.5 °F), range, midpoint shown (CAMEO).

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