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

Mercury difulminate

Mercury difulminate is a grey, pale brown or white crystalline solid.

CAS 628-86-4 C2HgN2O2 284.63 g/mol Danger

01 · Identification

What Mercury difulminate is

Mercury difulminate is a grey, pale brown or white crystalline solid. Its molecular formula is C2HgN2O2 and its molecular weight is 284.63 g/mol.

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

CAS number628-86-4
EC number211-057-8
Index number080-005-00-2
Molecular formulaC2HgN2O2
Molecular weight284.63 g/mol
Chemical class Flammable agents - 3rd degree

Other names for Mercury difulminate

  • mercuric fulminate
  • fulminate of mercury

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 Mercury difulminate
CodeHazard statement
H200 Unstable explosives.
H331 Toxic if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
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>.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P210, P260, P270, P271, P273, P280, P301, P302, P304, P310, P314, P330, P352, P391, P501

03 · Physical and chemical properties

Mercury difulminate 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 Explodes HSDB
Density 4.42 g/cm³ at 20 °C HSDB
Solubility Soluble in alcohol, ammonium hydroxide, and hot water; slightly soluble in cold water HSDB
In water, 100 mg/L at 15.5 °C at 15.5 °C HSDB
Lower explosive limit (LEL) An explosive sensitive to flame, heat, impact, friction, intense radiation, or contact with sulfuric acid. Self-explodes. HSDB

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

04 · Handling and storage

Storing and handling Mercury difulminate

Storage conditions

Explodes readily when dry, keep moist till use.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible with sulfuric acid.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Contact with sulfuric acid causes explosion, [Urbanski, 1967, vol. 3, 135, 149]. Aqueous ammonia and Hg react to form an explosive solid, likely a fulminate. (Thodos, G. Amer. Inst. Chen. Engrs. J., 1964, 10, 274.).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Mercury difulminate in the storage compatibility matrix →

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