Calcium hydroxide
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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, but unrelated to the citrus fruit (lime)) is slaked with water. A traditional name for calcium hydroxide is slaked lime. It is also called 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 many varied uses as:
- a form of lime, in water and sewage treatment and improvement of acid soils
- the tanning of leather
- an ingredient in whitewash, mortar, and plaster
- 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
- for neutralization of sour environments, in particular the sewage dumped in reservoirs
- in the food-processing industry for processing water (by manufacture alcoholic and soft drinks)
- in agro chemistry for processing sour soil
- 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 [1] (http://www.gourmetsleuth.com/pDetail.asp?p=154). 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 protection of agricultural crops from pests (bordeaux a mix)
- in manufacturing a drug called "Polikar" for fighting decay (due to fungus) of vegetables and fruits during storage
Risks
An overdose of calcium hydroxide can have many dangerous symptoms, including:
- difficulty breathing
- gastrointestinal bleeding
- hypotension
- a severe change in blood pH, which is damaging to the internal organs.ja:水酸化カルシウム