Names | |
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IUPAC name Potassium carbonate | |
Other names Carbonate of potash, dipotassium carbonate, sub-carbonate of potash, pearl ash, potash, salt of tartar, salt of wormwood. | |
Identifiers | |
3D model (JSmol) | |
ChEBI | |
ChemSpider | |
ECHA InfoCard | 100.008.665 |
E number | E501(i) (acidity regulators, ...) |
PubChem CID | |
RTECS number |
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UNII |
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CompTox Dashboard (EPA) | |
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Properties | |
K 2CO 3 | |
Molar mass | 138.205 g/mol |
Appearance | White, hygroscopic solid |
Density | 2.43 g/cm3 |
Melting point | 891 °C (1,636 °F; 1,164 K) |
Boiling point | Decomposes |
110.3 g/100 mL (20 °C) 149.2 g/100 mL (100 °C) | |
Solubility | |
Acidity (pKa) | 10.25 |
−59.0·10−6 cm3/mol | |
Thermochemistry [1] | |
Heat capacity (C) | 114.4 J·mol−1·K−1 |
Std molar entropy (S⦵298) | 155.5 J·mol−1·K−1 |
Std enthalpy of formation (ΔfH⦵298) | −1151.0 kJ·mol−1 |
Gibbs free energy (ΔfG⦵) | −1063.5 kJ·mol−1 |
Enthalpy of fusion (ΔfH⦵fus) | 27.6 kJ·mol−1 |
Hazards | |
GHS labelling: | |
Warning | |
H302, H315, H319, H335 | |
P261, P305+P351+P338 | |
NFPA 704 (fire diamond) | |
Flash point | Non-flammable |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose) | 1870 mg/kg (oral, rat) [2] |
Safety data sheet (SDS) | ICSC 1588 |
Related compounds | |
Other anions | Potassium bicarbonate |
Other cations | Lithium carbonate Sodium carbonate Rubidium carbonate Caesium carbonate |
Related compounds | Ammonium carbonate |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Potassium carbonate is the inorganic compound with the formula K2 CO3. It is a white salt, which is soluble in water and forms a strongly alkaline solution. It is deliquescent, often appearing as a damp or wet solid. Potassium carbonate is mainly used in the production of soap and glass. [3] Commonly, it can be found as the result of leakage of alkaline batteries. [4]
Potassium carbonate is the primary component of potash and the more refined pearl ash or salts of tartar. Historically, pearl ash was created by baking potash in a kiln to remove impurities. The fine, white powder remaining was the pearl ash. The first patent issued by the US Patent Office was awarded to Samuel Hopkins in 1790 for an improved method of making potash and pearl ash. [5]
In late 18th-century North America, before the development of baking powder, pearl ash was used as a leavening agent for quick breads. [6] [7]
The modern commercial production of potassium carbonate is by reaction of potassium hydroxide with carbon dioxide: [3]
From the solution crystallizes the sesquihydrate K2CO3·3⁄2H2O ("potash hydrate"). Heating this solid above 200 °C (392 °F) gives the anhydrous salt. In an alternative method, potassium chloride is treated with carbon dioxide in the presence of an organic amine to give potassium bicarbonate, which is then calcined:
Ash or ashes are the solid remnants of fires. Specifically, ash refers to all non-aqueous, non-gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash is the non-gaseous, non-liquid residue after complete combustion.
In inorganic chemistry, bicarbonate is an intermediate form in the deprotonation of carbonic acid. It is a polyatomic anion with the chemical formula HCO−
3.
A carbonate is a salt of carbonic acid, H2CO3, characterized by the presence of the carbonate ion, a polyatomic ion with the formula CO2−3. The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate groupO=C(−O−)2.
Potash includes various mined and manufactured salts that contain potassium in water-soluble form. The name derives from pot ash, plant ashes or wood ash soaked in water in a pot, the primary means of manufacturing potash before the Industrial Era. The word potassium is derived from potash.
Sodium bicarbonate (IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda, is a chemical compound with the formula NaHCO3. It is a salt composed of a sodium cation (Na+) and a bicarbonate anion (HCO3−). Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite, although it is more commonly found as a component of the mineral trona.
Sodium carbonate is the inorganic compound with the formula Na2CO3 and its various hydrates. All forms are white, odourless, water-soluble salts that yield alkaline solutions in water. Historically, it was extracted from the ashes of plants grown in sodium-rich soils, and because the ashes of these sodium-rich plants were noticeably different from ashes of wood, sodium carbonate became known as "soda ash". It is produced in large quantities from sodium chloride and limestone by the Solvay process, as well as by carbonating sodium hydroxide which is made using the Chlor-alkali process.
Baking powder is a dry chemical leavening agent, a mixture of a carbonate or bicarbonate and a weak acid. The base and acid are prevented from reacting prematurely by the inclusion of a buffer such as cornstarch. Baking powder is used to increase the volume and lighten the texture of baked goods. It works by releasing carbon dioxide gas into a batter or dough through an acid–base reaction, causing bubbles in the wet mixture to expand and thus leavening the mixture. The first single-acting baking powder was developed by food manufacturer Alfred Bird in England in 1843. The first double-acting baking powder, which releases some carbon dioxide when dampened and later releases more of the gas when heated by baking, was developed by Eben Norton Horsford in the U.S. in the 1860s.
Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash.
Potassium bicarbonate (IUPAC name: potassium hydrogencarbonate, also known as potassium acid carbonate) is the inorganic compound with the chemical formula KHCO3. It is a white solid.
Magnesium carbonate, MgCO3, is an inorganic salt that is a colourless or white solid. Several hydrated and basic forms of magnesium carbonate also exist as minerals.
Ammonium bicarbonate is an inorganic compound with formula (NH4)HCO3. The compound has many names, reflecting its long history. Chemically speaking, it is the bicarbonate salt of the ammonium ion. It is a colourless solid that degrades readily to carbon dioxide, water and ammonia.
The Leblanc process was an early industrial process for making soda ash used throughout the 19th century, named after its inventor, Nicolas Leblanc. It involved two stages: making sodium sulfate from sodium chloride, followed by reacting the sodium sulfate with coal and calcium carbonate to make sodium carbonate. The process gradually became obsolete after the development of the Solvay process.
Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 million tonnes, the decahydrate is a major commodity chemical product. It is mainly used as a filler in the manufacture of powdered home laundry detergents and in the Kraft process of paper pulping for making highly alkaline sulfides.
Barium carbonate is the inorganic compound with the formula BaCO3. Like most alkaline earth metal carbonates, it is a white salt that is poorly soluble in water. It occurs as the mineral known as witherite. In a commercial sense, it is one of the most important barium compounds.
Ammonium carbonate is a chemical compound with the chemical formula [NH4]2CO3. It is an ammonium salt of carbonic acid. It is composed of ammonium cations [NH4]+ and carbonate anions CO2−3. Since ammonium carbonate readily degrades to gaseous ammonia and carbon dioxide upon heating, it is used as a leavening agent and also as smelling salt. It is also known as baker's ammonia and is a predecessor to the more modern leavening agents baking soda and baking powder. It is a component of what was formerly known as sal volatile and salt of hartshorn, and produces a pungent smell when baked. It comes in the form of a white powder or block, with a molar mass of 96.09 g/mol and a density of 1.50 g/cm3. It is a strong electrolyte.
Chemical decomposition, or chemical breakdown, is the process or effect of simplifying a single chemical entity into two or more fragments. Chemical decomposition is usually regarded and defined as the exact opposite of chemical synthesis. In short, the chemical reaction in which two or more products are formed from a single reactant is called a decomposition reaction.
Potassium fluoride is the chemical compound with the formula KF. After hydrogen fluoride, KF is the primary source of the fluoride ion for applications in manufacturing and in chemistry. It is an alkali halide salt and occurs naturally as the rare mineral carobbiite. Solutions of KF will etch glass due to the formation of soluble fluorosilicates, although HF is more effective.
Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group [R−N+≡N]X− where R can be any organic group, such as an alkyl or an aryl, and X is an inorganic or organic anion, such as a halide. The parent compound where R is hydrogen, is diazenylium.
Condensed aerosol fire suppression is a particle-based method of fire extinction. It is similar to but not identical to dry chemical fire extinction methods, using an innovative pyrogenic, condensed aerosol fire suppressant. It is a highly effective fire suppression method for class A, B, C, E and F. Some aerosol-generating compounds produce a corrosive by-product that may damage electronic equipment, although later generations lower the effect.
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