Calcium hydroxide

From Freepedia

Image:Calcium hydroxide.jpg 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 slaked with water. A traditional name for calcium hydroxide is slaked lime, or hydrated lime.

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

Uses

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 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 cooking, used to make corn easier to grind; cooks call it cal and the processed corn Nixtamal
• 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

Health risks

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

• difficulty breathing
• Internal bleeding
• hypotension
• a severe change in blood pH, which is damaging to the internal organs.