Calcium hydroxide
General
Systematic name	Calcium hydroxide
Other names	Calcium(II) hydroxide, slaked lime, hydrated lime.
Molecular formula	Ca(OH)2
Molar mass	74.093 g/mol
Appearance	Soft white powder.
Crystal Structure	hexagonal
CAS number	*
Properties
Density and phase	2.24 g/cm3, solid
Solubility in water	0.185g/100 cc Water. Ksp=4.68E-6
Melting point	580°C (Decomposes).
Boiling point	N/A
Basicity (pKb)	N/A
Specific Heat Capacity	1.18095 J/g-°C
Heat of formation	-985.2 kJ/mol
Hazards
MSDS	External MSDS
EU classification	Corrosive (C)
R-phrases	, , , , .
S-phrases	, , , .
NFPA 704	N/A
Flash point	Non-flammable.
Supplementary data page
Structure and properties	n, εr, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Other anions	None listed.
Other cations	None listed.
Related bases	Calcium oxide.
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Chemical infobox

Calcium hydroxide is a chemical compound with the chemical formula Ca(OH)₂. It is a colorless crystal or white powder, and is created when calcium oxide (called lime or quicklime) is slake with water. It can also be created by mixing an aqueous solution of calcium chloride and an aqueous solution of sodium hydroxide. A traditional name for calcium hydroxide is slaked lime, or hydrated lime.

If heated, calcium hydroxide decomposes into calcium oxide and water. A suspension of fine calcium hydroxide particles in water, called lime water (or milk of lime), is a medium strength base that reacts violently with acids and attacks many metals in presence of water.

Uses

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Because of its strong basic properties, calcium hydroxide has varied uses, such as:

• A form of lime, in water and sewage treatment and improvement of acid soils
• An ingredient in whitewash, mortar, and plaster
• An alkaline used as a lye substitute in no-lye hair relaxers
• A reagent
  • In the reef aquarium hobby for adding bio-available calcium in solution for calcium-using animals such as algaes, snails, hard tube worms and corals (often referred to as Kalkwasser mix)
  • In the tanning industry for neutralization of extra acid
  • In the petroleum refining industry for the manufacture of additives to oils (alkilsalicatic, sulphatic, fenatic)
  • In the chemical industry for manufacture of calcium stearate
  • In the food industry for processing water (for alcoholic and soft drinks)
  • For clearing a brine of carbonates of calcium and magnesium in the manufacture of salt for food and pharmacopoeia
  • In Native American and Latin American cooking, calcium hydroxide is called "cal." Corn cooked with cal becomes nixtamal, which is considered tastier and easier to digest.
• A filler
  • In the petrochemical industry for manufacturing solid oil of various marks
  • In the manufacture of brake pads
  • In the manufacture of ebonite
  • For preparation of dry mixes for painting and decorating
  • In manufacturing mixes for pesticides
  • In manufacturing a drug called "Polikar" for fighting decay (due to fungus) of fruits and vegetables during storage
• A paste used to fill the inside of a tooth during a root canal procedure, left in for a period of weeks, to disinfect and reduce inflammation in surrounding material.^*

Health risks

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An overdose of calcium hydroxide can have dangerous symptoms, including:

• Difficulty in breathing
• Internal bleeding
• Hypotension
• Skeletal muscle paralysis, interferance with actin-myosin system.
• An increase in blood pH, which is damaging to the internal organs.

External links

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• http://www.omri.org/CaOH_final.pdf
• MSDS Data Sheet.

Calcium compounds | Hydroxides | Inorganic compounds

Kalziumhydroxid | Kaltsiumhüdroksiid | Chaux (chimie) | Calciumhydroxide | 水酸化カルシウム | Гидроксид кальция