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

2,4-Dinitrophenol

2,4-Dinitrophenol is pale yellow platelets or leaflets from water with a sweet, musty odor.

CAS 51-28-5 C6H4N2O5 184.11 g/mol Danger

01 · Identification

What 2,4-Dinitrophenol is

2,4-Dinitrophenol is pale yellow platelets or leaflets from water with a sweet, musty odor. Its molecular formula is C6H4N2O5 and its molecular weight is 184.11 g/mol. It melts at 115 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number51-28-5
EC number200-087-7
Index number609-041-00-4
Molecular formulaC6H4N2O5
Molecular weight184.11 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

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 2,4-Dinitrophenol
CodeHazard statement
H300 Fatal if swallowed.
H331 Toxic if inhaled.
H311 Toxic in contact with skin.
H372 Causes damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H400 Very toxic to aquatic life.

Precautionary statements: P260, P270, P271, P273, P280, P301, P302, P304, P310, P314, P330, P352, P391, P501

03 · Physical and chemical properties

2,4-Dinitrophenol 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
Boiling point Sublimes sublimes HSDB
Sublimes (when carefully heated) (NTP, 1992) sublimes CAMEO
Melting point 114.8 °C (238.6 °F) HSDB
112 °C (233.6 °F) ICSC
Density 1.68 g/cm³ ICSC
1.683 g/cm³ at 24 °C HSDB
1.68 g/cm³ at 20 °C CAMEO
Solubility Soluble in ethanol, ethyl ether, benzene, methanol HSDB
Soluble in aqueous alkaline solutions HSDB
In water, 5,600 mg/L at 18 °C; 43,000 mg/L at 100 °C at 18 °C HSDB
Vapor pressure 0.00039 mmHg at 20 °C HSDB
0.00039 mmHg Haz-Map
Lower explosive limit (LEL) Dust explosion possible if in powder or granular form, mixed with air. HSDB
Forms explosive salts with alkalies and ammonia. HSDB
Prolonged exposure to fire or heat may result in the spontaneous decomposition and heating with a resultant explosion. decomposes, Dinitrophenol solutions HSDB
Vapor density 6.35 (air = 1) HSDB
6.36 (air = 1) ICSC

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

04 · Handling and storage

Storing and handling 2,4-Dinitrophenol

Storage conditions

/Dinitrophenol/ ... should be stored in a cool ventilated place away from area of acute fire hazard and away from powerful oxidizing agents. /Dinitrophenol/

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Contact with reducing agents, combustibles may cause fire and explosions. Forms shock-sensitive explosive salts with ammonia, strong bases, and most metals. May accumulate static electrical charges /which/ may cause ignition of its vapors.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

2,4-DINITROPHENOL may explode if subjected to heat or flame. May explode if allowed to dry out. Forms explosive salts with alkalis and ammonia. Incompatible with heavy metals and their compounds. Also incompatible with strong oxidizing agents, strong bases and reducing agents. Reacts with combustibles. (NTP, 1992)

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 2,4-Dinitrophenol in the storage compatibility matrix →

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