POTASSIUM HYDROXIDE

Potassium Hydroxide
Potassium hydroxide
General
Other names	Potash lye
Molecular formula	KOH
Molar mass	56.10564 g/mol
Appearance	white solid, deliquescent
CAS number	[1310-58-3]
Properties
Density and phase	2.044 g/cm³, solid
Solubility in water	1100 g/L (25 °C)
Melting point	360 °C
Boiling point	1320 °C
Vapour Pressure	1.3hPa (719 ° C)
Basicity (p''K''b)	-2.29
Structure
Coordination geometry	?
Crystal structure	monoclinic
Hazards
MSDS	External MSDS
EU classification	Corrosive ('C')
NFPA 704
R-phrases	,
S-phrases	, , ,
Flash point	non flammable
RTECS number	TT2100000
Supplementary data page
Structure and properties	''n'', εr, etc.
Thermodynamic data	Phase behaviour: Solid
Spectral data	UV, IR, NMR, MS
Related compounds
Other anions	Potassium oxide Potassium peroxide Potassium superoxide
Other cations	Lithium hydroxide Sodium hydroxide Rubidium hydroxide Caesium hydroxide
Except where noted otherwise,data are given for materials in their standard state (at 25 °C, 100 kPa)

The chemical compound 'potassium hydroxide' (KOH), sometimes known as 'caustic potash', 'potassa', 'potash lye', and 'potassium hydrate', is a metallic base. It is very alkaline and is a "strong base", along with sodium hydroxide, lithium hydroxide, calcium hydroxide, barium hydroxide and strontium hydroxide.

Contents

Uses

Agriculture

Manufacturing and commercial chemical processes

Medicine (human and veterinary)

Food preparation

See also

External links

Uses

Agriculture

★ Correction of the pH of acidic soils

★ As a fungicide

★ As an herbicide

Manufacturing and commercial chemical processes

KOH is a major industrial chemical because it is used as a base in a wide variety of chemical processes. Some uses of KOH include:

★ Acrylate ester copolymer coating

★ defoaming agents used in the manufacture of paper

★ saponifying oils for liquid soap

★ Formulation aid for food

★ pH control agent (raises pH by neutralizing acids)

★ Making polyethylene resins

★ Textile processing

★ As a catalyst in reactions like the production of biodiesel.

★ Manufacture of many cleaning products, such as:

★
★ Washing powders

★
★ Cleansers (for tubs, tile, etc)

★
★ Some denture cleaners

★
★ Non-phosphate detergents

★
★ Drain or pipe cleaners (clog dissolvers)

★ Manufacture of alkaline batteries, which use an aqueous solution of KOH as an electrolyte. Thus, potassium hydroxide helps to power flashlights, smoke detectors, and other battery-powered household items.

★ As an anisotropic etchant of silicon, exposing octahedral planes. This technique can create pyramids and regularly-shaped etch pits for uses such as microelectromechanical systems.

Medicine (human and veterinary)

★ KOH test (to diagnose fungal infections)

★ Whiff test (to diagnose bacterial vaginosis)

★ wart and cuticle solvent

★ (''veterinary medicine'') disbudding calves horns; dissolving scales and hair

Food preparation

Food uses of lye include:

★ Washing or chemical peeling of fruits and vegetables

★ Chocolate and cocoa processing

★ Caramel color production

★ Poultry scalding

★ Soft drink processing

★ Thickening ice cream

★ Soaking of olives to soften them and neutralize natural acids

★ Glazing of pretzels and German lye rolls before baking to make them crisp.

★ Soaking of cod to make the Scandinavian delicacy known as lutefisk (from ''lutfisk'', "lye fish"). Cod is soaked in lye to a jelly-like consistency, then served with bacon fat, potatoes, brown cheese (brunost) sauce and mushy peas.

★ Making of hominy, which is dried maize (corn) kernels reconstituted by soaking in lye.

See also

★ Soda lime

External links

★ Newscientist article dn10104

★ MSDS from JTBaker

★ Reheis [1]

★ Making lye from ashes