Calcium Hydroxide >95%




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Calcium hydroxide, traditionally called slaked lime, is an inorganic compound with the chemical formula Ca(OH)2. It is a colourless crystal or white powder and is obtained when calcium oxide (called lime or quicklime) is mixed, or “slaked” with water. It has many names including Reef Kalkwasser, hydrated lime, builders lime, slack lime, cal, or pickling lime. It is of low toxicity and finds many applications.

  • A flocculant, in water and sewage treatment and improvement of acid soils
  • An ingredient in whitewash, mortar, and plaster
  • An alkali used as a lye substitute in no-lye hair relaxers
  • For reef aquarium hobby for adding bio-available calcium in solution for calcium-using animals such as algae, snails, hard tube worms, and corals (often referred to as Kalkwasser mix), and also to increase the alkalinity of the water

Molecular Formula: Ca(OH)2
Molecular Weight: 74.09 g/mol
Melting Point: 550°C
Density at 25°C (g/cm3): 2.24
pH (saturated soln 20°C): 12.6
Calcium Hydroxide (Ca(OH)2): >95%
Calcium Carbonate (CaCO3): >0.55%
Magnesium Oxide (MgO:) <0.23%
Iron Oxide (Fe2O3): <0.03%
Aluminium Oxide (Al2O3): <0.04%
Silica (SiO2): <0.36%
Manganese (Mn)
Sulphur (S): <0.01%
Free Moisture: 0.53%
Available Lime (as Ca(OH)2): >95%
Neutralisation: 74.46%

Hazard Phrases: Causes skin irritation. Causes serious eye damage. May cause respiratory irritation.

Prec Phrases: Avoid breathing dust/fume/gas/mist/vapours/spray. Wear protective gloves/protective clothing/eye protection/face protection. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.


Cas No: 1305-62-0
Einecs No: 215-137-3
FP: Not Flammable

HS CODE: 2825900000


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The Duty is ascertained by your national customs authority based on the HS Code of each product. The HS Code is shown in the “European Shipment” section of each product page.


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