Sodium percarbonate
Encyclopedia
Sodium percarbonate is a chemical
Chemical substance
In chemistry, a chemical substance is a form of matter that has constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e. without breaking chemical bonds. They can be solids, liquids or gases.Chemical substances are...

, an adduct
Adduct
An adduct is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all components. The resultant is considered a distinct molecular species...

 of sodium carbonate
Sodium carbonate
Sodium carbonate , Na2CO3 is a sodium salt of carbonic acid. It most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. Sodium carbonate is domestically well-known for its everyday use as a water softener. It can be extracted from the...

 and hydrogen peroxide
Hydrogen peroxide
Hydrogen peroxide is the simplest peroxide and an oxidizer. Hydrogen peroxide is a clear liquid, slightly more viscous than water. In dilute solution, it appears colorless. With its oxidizing properties, hydrogen peroxide is often used as a bleach or cleaning agent...

 (a perhydrate), with formula Na2CO3 · 1.5H2O2. It is a colorless, crystalline, hygroscopic and water-soluble solid. It is used in some eco-friendly cleaning products and as a laboratory source of anhydrous
Anhydrous
As a general term, a substance is said to be anhydrous if it contains no water. The way of achieving the anhydrous form differs from one substance to another...

 hydrogen peroxide.

This product contains the carbonate
Carbonate
In chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, . The name may also mean an ester of carbonic acid, an organic compound containing the carbonate group C2....

 anion, and should not be confused with sodium peroxocarbonate
Peroxocarbonate
In chemistry, peroxocarbonate is a divalent anion with formula CO42−. It is an oxocarbon anion that consists solely of carbon and oxygen. It would be the anion of an hypothetical peroxocarbonic acid HO–CO–O–OH....

 Na2CO4 or peroxodicarbonate
Peroxodicarbonate
In chemistry, peroxodicarbonate is a divalent anion with formula C2O62−. It is one of the oxocarbon anions, that consist solely of carbon and oxygen...

 Na2C2O6, which contain different anions.

Structure

At room temperature, solid sodium percarbonate has the orthorhombic crystal structure
Crystal structure
In mineralogy and crystallography, crystal structure is a unique arrangement of atoms or molecules in a crystalline liquid or solid. A crystal structure is composed of a pattern, a set of atoms arranged in a particular way, and a lattice exhibiting long-range order and symmetry...

, with the Cmca crystallographic space group
Space group
In mathematics and geometry, a space group is a symmetry group, usually for three dimensions, that divides space into discrete repeatable domains.In three dimensions, there are 219 unique types, or counted as 230 if chiral copies are considered distinct...

. The structure changes to Pbca as the crystals are cooled below about −30 °C.

Production

Sodium percarbonate is produced industrially by reaction of sodium carbonate and hydrogen peroxide, followed by crystallization. Also, dry sodium carbonate may be reacted directly with concentrated hydrogen peroxide solution. World production capacity of this compound was estimated at several hundred thousand tonnes for 2004. It can be obtained in the laboratory by reacting the two substances in aqueous solution with proper control of the pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

 or concentrations.

Uses

Sodium percarbonate is an oxidizing agent
Oxidizing agent
An oxidizing agent can be defined as a substance that removes electrons from another reactant in a redox chemical reaction...

 and ingredient in a number of home and laundry cleaning
Laundry detergent
Laundry detergent, or washing powder, is a substance that is a type of detergent that is added for cleaning laundry. In common usage, "detergent" refers to mixtures of chemical compounds including alkylbenzenesulfonates, which are similar to soap but are less affected by "hard water." In most...

 products, including bleach
Bleach
Bleach refers to a number of chemicals that remove color, whiten, or disinfect, often via oxidation. Common chemical bleaches include household chlorine bleach , lye, oxygen bleach , and bleaching powder...

 products such as OxiClean
OxiClean
-History:It was originally marketed through infomercials in the U.S. and Canada with Billy Mays, as a "miracle cleanser". Church and Dwight acquired the OxiClean brand through its acquisition of Orange Glo International in 2006. Endorsed by Mays until his death in 2009, the product is now seen...

 and Tide laundry detergent
Tide (detergent)
Tide is the brand-name of a popular laundry detergent manufactured by Procter & Gamble and first introduced to the United States consumer in 1946. It is also marketed in Canada, Saudi Arabia, Morocco, India and several other countries...

. It contains no phosphorus or nitrogen. Dissolved in water, it yields a mixture of hydrogen peroxide (which eventually decomposes to water and oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

) and sodium carbonate ("soda ash").

Sodium percarbonate can be used in organic synthesis
Organic synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the construction of organic compounds via organic reactions. Organic molecules can often contain a higher level of complexity compared to purely inorganic compounds, so the synthesis of organic compounds has...

as a convenient source of anhydrous H2O2, in particular in solvents that cannot dissolve the carbonate but can leach the H2O2 out of it.

External links

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