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

Calcium hypochlorite

Calcium hypochlorite is a powder with a strong chlorine odor.

CAS 7778-54-3 CaCl2O2 142.98 g/mol Danger

Calcium hypochlorite Safety Data Sheet →

01 · Identification

What Calcium hypochlorite is

Calcium hypochlorite is a powder with a strong chlorine odor. Its molecular formula is CaCl2O2 and its molecular weight is 142.98 g/mol. It boils at 100 °C, melts at 100 °C.

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

CAS number7778-54-3
EC number231-908-7
Index number017-012-00-7
Molecular formulaCaCl2O2
Molecular weight142.98 g/mol
Chemical class Reactive agents - 1st degree

Other names for Calcium hypochlorite

  • pool chlorine
  • cal hypo
  • Ca(ClO)2

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 Calcium hypochlorite
CodeHazard statement
H272 May intensify fire; oxidiser.
H302 Harmful if swallowed.
H314 Causes severe skin burns and eye damage.
H400 Very toxic to aquatic life.

Supplemental EU statements: EUH031

Precautionary statements: P260, P270, P273, P280, P301, P310, P312, P330, P331, P391, P501

03 · Physical and chemical properties

Calcium hypochlorite 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 100 °C (212 °F) decomposes HSDB
Melting point 100 °C (212 °F) HSDB
Density 2.35 g/cm³ HSDB
2.35 g/cm³ at 25 °C DOE PAC
Solubility 21% in water at 25 °C at 25 °C HSDB
Solubility in water, g/100ml at 25 °C: 21 at 25 °C ICSC
Corrosivity 0.001 mm ASTM grade 2 titanium/yr at 6 wt% and 100 °C From table HSDB

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

04 · Handling and storage

Storing and handling Calcium hypochlorite

Storage conditions

Store in a cool, dry, well-ventilated location at a temperature below 120 °F (50 °C) to avoid slow decomposition. Separate from oxidizing materils, acids, ammonia, amines, and other chlorinating agents. Immediately remove and properly dispose of any spilled material. /Calcium hypochlorite, dry or calcium hypochlorite, mixtures, dry/

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Reacts with water and with acids releasing chlorine. Forms explosive compounds with ammonia and amines. Strong oxidizer. Other incompatible materials include organics, nitrogen containing compounds, dry chemical fire extinguishers containing mono-ammonium phosphate, combustible or flammable materials. /Calcium hypochlorite, dry or calcium hypochlorite, mixtures, dry/

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

BLEACHING POWDER is a strong oxidizing agent and a base. Acts in aqueous solution by releasing hypochlorite ion (OCl- ion). Decomposes on standing to give oxygen (a strong oxidizing agent) and calcium chloride. Mixing of bleaching powder (hypochlorite solution) with ammonia solutions produces toxic/explosive ammonia trichloride vapors.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Calcium hypochlorite in the storage compatibility matrix →

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