Trisodium borate is a

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

sodium Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable iso ...

boron Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has th ...

, and

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

, with

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwee ...

, or . It is a

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...

with the

orthoborate In inorganic chemistry, an orthoborate is a polyatomic anion with formula or a salt containing the anion; such as trisodium orthoborate . It is one of several boron oxoanions, or borates. The name is also used in organic chemistry for the trival ...

anion . The compound is also called trisodium orthoborate, sodium orthoborate, or just sodium borate. However, "sodium orthoborate" has been used also for a compound with formula , which would correspond to an

equimolar This glossary of chemistry terms is a list of terms and definitions relevant to chemistry, including chemical laws, diagrams and formulae, laboratory tools, glassware, and equipment. Chemistry is a physical science concerned with the composition, ...

mixture of

sodium metaborate Sodium metaborate is a chemical compound of sodium, boron, and oxygen with formula . However, the metaborate ion is trimeric in the anhydrous solid, therefore a more correct formula is or . The formula can be written also as · to highlight the ...

and trisodium borate proper. and "sodium borate" is sometimes used in the generic sense, for a sodium salt with any of several other

borate A borate is any of several boron oxyanions, negative ions consisting of boron and oxygen, such as orthoborate , metaborate , or tetraborate ; or any salt with such anions, such as sodium metaborate, and disodium tetraborate . The name also refe ...

anions.

Preparation

Sodium carbonate will react with sodium metaborate or boric oxide to form the orthoborate and

carbon dioxide Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...

when heated between 600 and 850 °C: : + → + Difficult to obtain in pure form from melts.

Properties

Reactions

When dissolved in water, the orthoborate anion partially

hydrolyzes Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis ...

into metaborate and

hydroxide Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. I ...

: : + + 3

Electrolysis In chemistry and manufacturing, electrolysis is a technique that uses direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction. Electrolysis is commercially important as a stage in the separation of elements from n ...

of a solution of sodium orthoborate generates

sodium perborate Sodium perborate is chemical compound whose chemical formula may be written , , or, more properly, ·. Its name is sometimes abbreviated as PBS (not to be confused with phosphate-buffered saline). The compound is commonly encountered in anhydro ...

at the

anode An anode is an electrode of a polarized electrical device through which conventional current enters the device. This contrasts with a cathode, an electrode of the device through which conventional current leaves the device. A common mnemonic is ...

References

G. W. Morey and H. E. Merwin (1936): "Phase Equilibrium Relationships in the Binary System, Sodium Oxide-Boric Oxide, with Some Measurements of the Optical Properties of the Glasses". ''Journal of the American Chemical Society'', volume 58, issue 11, pages 2248–2254. Pasupathy Rajan Subbaiyan (2003): "Study of Trisodium Borate Formation and Its Reaction with Green Liquor in Partial Autocausticizing". Masters Thesis, Western Michigan University. "Trisodium borate"
Product page in the ''World Of Chemicals'' website. Accessed on 2022-06-27. Daniel L. Calabretta and Boyd R. Davis (2007) "Investigation of the anhydrous molten Na–B–O–H system and the concept: Electrolytic hydriding of sodium boron oxide species". ''Journal of Power Sources'', volume 164, issue 2, pages 782-791. Wilfrid Gustav Polack (1915): "The anodic behaviour of alkaline borate and perborate solutions". ''Transactions of the Faraday Society'', volume 10, pages 177-196. Tanatar (1898): ''Zh. Pys. Chem.'', volume 26, page 132. {{chem-stub Chemical compounds