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

Hydroxylamine ....% [> 55 % in aqueous solution]

Hydroxylamine ....% [> 55 % in aqueous solution] is colorless cyrstals.

CAS 7803-49-8 H3NO 33.03 g/mol Danger

01 · Identification

What Hydroxylamine ....% [> 55 %… is

Hydroxylamine ....% [> 55 % in aqueous solution] is colorless cyrstals. Its molecular formula is H3NO and its molecular weight is 33.03 g/mol. It boils at 56.5 °C, melts at 33 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as reactive agents - 3rd degree.

CAS number7803-49-8
EC number232-259-2
Index number612-122-00-7
Molecular formulaH3NO
Molecular weight33.03 g/mol
Chemical class Reactive agents - 3rd degree

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 Hydroxylamine ....% [> 55 %…
CodeHazard statement
H200 Unstable explosives.
H290 May be corrosive to metals.
H351 Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H312 Harmful in contact with skin.
H302 Harmful if swallowed.
H335 May cause respiratory irritation.
H373 May cause 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>.
H315 Causes skin irritation.
H318 Causes serious eye damage.
H317 May cause an allergic skin reaction.
H400 Very toxic to aquatic life.

Precautionary statements: P201, P210, P260, P261, P264, P270, P272, P273, P280, P301, P302, P305, P308, P310, P312, P313, P314, P330, P332, P333, P338, P352, P391, P501

03 · Physical and chemical properties

Hydroxylamine ....% [> 55 %… 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 56.5 °C (133.7 °F) CAMEO
107 °C (224.6 °F) ICSC
58 °C (136.4 °F) at 760 mmHg DOE PAC
Melting point 33 °C (91.4 °F) HSDB
33.05 °C (91.5 °F) CAMEO
Density 1.227 g/cm³ HSDB
1.2 g/cm³ ICSC
1.227 g/cm³ at 20 °C CAMEO
Solubility Very sol in water, liq ammonia, methanol; sparingly sol in ether, benzene, carbon disulfide, chloroform HSDB
Soluble in alcohol, acids, and cold water HSDB
Solubility in water at 20 °C: freely soluble at 20 °C ICSC
Vapor pressure 10.5009 mmHg at 20 °C ICSC
53 mmHg at 32 °C HSDB
Flash point 129.44 °C (265 °F) CAMEO
129 °C (264.2 °F) ICSC
Autoignition temperature 129.44 °C (265 °F) CAMEO
215 °C (419 °F) ICSC
Lower explosive limit (LEL) Noncombustible solid that explodes when heated to 265 °F (129 °C). ... It will decompose at high temperatures and, if confined at 284 °F (140 °C), will explode. decomposes, at 140 °C HSDB
Vapor density 1.1 (air = 1) ICSC

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

04 · Fire and explosion

Fire and explosion behaviour of Hydroxylamine ....% [> 55…

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.

Fire and explosion

Explosive reaction with potassium dichromate; chromium trioxide; powdered zinc + heat. Forms the heat sensitive explosive bis(hydroxylamide) in reaction with zinc or calcium.

Source: HSDB

05 · Handling and storage

Storing and handling Hydroxylamine ....% [> 55 %…

Storage conditions

Separate from oxidizing materials. store in a cool, dry, well-ventilated location. store away from heat, oxidizers, and sunlight. Outside or detached storage is preferred.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible with carbonyls; pyridine. Vigorous reaction with hypochlorites.

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check Hydroxylamine ....% [>… in the storage compatibility matrix →

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