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

Magnesium powder (pyrophoric)

Magnesium powder (pyrophoric) is a silvery-white metal with a none odor.

CAS 7439-95-4 Danger

01 · Identification

What Magnesium powder (pyrophoric) is

Magnesium powder (pyrophoric) is a silvery-white metal with a none odor. It boils at 1100 °C, melts at 651 °C, is practically insoluble in water.

Under the GHS it carries the signal word Danger. It is classed as reactive agents - 1st degree.

CAS number7439-95-4
EC number231-104-6
Index number012-001-00-3
Chemical class Reactive agents - 1st 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 Magnesium powder (pyrophoric)
CodeHazard statement
H250 Catches fire spontaneously if exposed to air.
H260 In contact with water releases flammable gases which may ignite spontaneously.

Precautionary statements: P210, P222, P231, P280, P370, P501

03 · Physical and chemical properties

Magnesium powder (pyrophoric) 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 1100 °C (2012 °F) HSDB
1100 °C (2012 °F) at 760 mmHg CAMEO
Melting point 651 °C (1203.8 °F) HSDB
650 °C (1202 °F) CAMEO
649 °C (1200.2 °F) ICSC
Density 1.7 g/cm³ ICSC
1.738 g/cm³ at 20 °C HSDB
1.74 g/cm³ at 20 °C CAMEO
Solubility INSOL IN COLD WATER, CHROMIUM TRIOXIDES; SOLUBLE IN MINERAL ACIDS HSDB
Insoluble but reactive in water, liberating hydrogen gas HSDB
Solubility in water: reaction ICSC
Vapor pressure 0.0075 mmHg at 428 °C HSDB
1 mmHg Haz-Map
Flash point 500 °C (932 °F) HSDB
Autoignition temperature 472.78 °C (883 °F) HSDB
473 °C (883.4 °F) ICSC
Lower explosive limit (LEL) ... Powders form explosive mixtures with air that may be ignited by a spark. HSDB
...MOLTEN METAL BURNS EXPLOSIVELY IN PRESENCE OF EXCESSIVE MOISTURE, AS IN MOULDING SAND. FIRE & EXPLOSION ARE OUTSTANDING HAZARDS IN MFR OF MAGNESIUM ALLOYS. HSDB
Explosive limits , vol% in air: ICSC
Vapor density 0.84 (air = 1) HSDB
Corrosivity Highly resistant HSDB

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

04 · Handling and storage

Storing and handling Magnesium powder (pyrophoric)

Storage conditions

Detached storage must be used for finely divided materials. Must be stored in a dry location. Isolate from halogens, acids, and oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible with ethylene oxide, metal oxosalts, oxidants, and potassium carbonate.

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check Magnesium powder… in the storage compatibility matrix →

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