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.

CAS number104-91-6
EC number203-251-6
Index number604-042-00-6
Molecular formulaC6H5NO2
Molecular weight123.11 g/mol

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 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.

Precautionary statements: P201, P270, P273, P280, P301, P305, P308, P310, P312, P313, P330, P338, P391, P501

03 · 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.

Property Value Conditions Source
Melting point 138.06 °C (280.5 °F) range, midpoint shown CAMEO
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
Vapor pressure 0.15 mmHg Haz-Map
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.

04 · Handling and storage

Storing 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 →

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