Potassium sodium tartrate

Last updated
Sodium potassium L(+)-tartrate tetrahydrate [1] [2]
K-Na-L-(+)-tartrate.png
Potassium-sodium-tartrate-tetrahydrate-xtal-3D-SF.png
Potassium Sodium Tartrate Tetrahydrate.jpg
Potassium sodium tartrate tetrahydrate
Names
IUPAC name
Sodium potassium L(+)-tartrate tetrahydrate
Other names
E337; Seignette's salt; Rochelle salt
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.132.041 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 206-156-8
E number E337 (antioxidants, ...)
PubChem CID
UNII
  • InChI=1S/C4H6O6.K.Na/c5-1(3(7)8)2(6)4(9)10;;/h1-2,5-6H,(H,7,8)(H,9,10);;/q;2*+1/p-2 Yes check.svgY
    Key: LJCNRYVRMXRIQR-UHFFFAOYSA-L Yes check.svgY
  • InChI=1/C4H6O6.K.Na/c5-1(3(7)8)2(6)4(9)10;;/h1-2,5-6H,(H,7,8)(H,9,10);;/q;2*+1/p-2
    Key: LJCNRYVRMXRIQR-NUQVWONBAG
  • [K+].[Na+].O=C([O-])C(O)C(O)C([O-])=O
Properties
KNaC4H4O6·4H2O
Molar mass 282.22 g/mol (tetrahydrate)
Appearancelarge colorless monoclinic needles
Odor odorless
Density 1.79 g/cm3
Melting point 75 °C (167 °F; 348 K)
Boiling point 220 °C (428 °F; 493 K) anhydrous at 130 °C; decomposes at 220 °C
26 g / 100 mL (0 °C); 66 g / 100 mL (26 °C)
Solubility in ethanolinsoluble
Structure
orthorhombic
Related compounds
Related compounds
Acid potassium tartrate; Aluminum tartrate; Ammonium tartrate; Calcium tartrate; Metatartaric acid; Potassium antimonyl tartrate; Potassium tartrate; Sodium ammonium tartrate; Sodium tartrate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Potassium sodium tartrate tetrahydrate, also known as Rochelle salt, is a double salt of tartaric acid first prepared (in about 1675) by an apothecary, Pierre Seignette, of La Rochelle, France. Potassium sodium tartrate and monopotassium phosphate were the first materials discovered to exhibit piezoelectricity. [3] This property led to its extensive use in crystal phonograph cartridges, microphones and earpieces during the post-World War II consumer electronics boom of the mid-20th century. Such transducers had an exceptionally high output with typical pick-up cartridge outputs as much as 2 volts or more. Rochelle salt is deliquescent so any transducers based on the material deteriorated if stored in damp conditions.

Contents

It has been used medicinally as a laxative. It has also been used in the process of silvering mirrors. It is an ingredient of Fehling's solution (reagent for reducing sugars). It is used in electroplating, in electronics and piezoelectricity, and as a combustion accelerator in cigarette paper (similar to an oxidizer in pyrotechnics). [2]

In organic synthesis, it is used in aqueous workups to break up emulsions, particularly for reactions in which an aluminium-based hydride reagent was used. [4] Sodium Potassium tartrate is also important in the food industry. [5]

It is a common precipitant in protein crystallography and is also an ingredient in the Biuret reagent which is used to measure protein concentration. This ingredient maintains cupric ions in solution at an alkaline pH.

Preparation

Large Rochelle salt crystal grown aboard Skylab Rochellesalt.jpg
Large Rochelle salt crystal grown aboard Skylab

The starting material is tartar with a minimum tartaric acid content 68 %. This is first dissolved in water or in the mother liquor of a previous batch. It is then basified with hot saturated sodium hydroxide solution to pH 8, decolorized with activated charcoal, and chemically purified before being filtered. The filtrate is evaporated to 42 °Bé at 100 °C, and passed to granulators in which Seignette's salt crystallizes on slow cooling. The salt is separated from the mother liquor by centrifugation, accompanied by washing of the granules, and is dried in a rotary furnace and sieved before packaging. Commercially marketed grain sizes range from 2000 μm to < 250 μm (powder). [2]

Larger crystals of Rochelle salt have been grown under conditions of reduced gravity and convection on board Skylab . [6] Rochelle salt crystals will begin to dehydrate when the relative humidity drops to about 30% and will begin to dissolve at relative humidities above 84%. [7]

Piezoelectricity

In 1824, Sir David Brewster demonstrated piezoelectric effects using Rochelle salts, [8] which led to him naming the effect pyroelectricity. [9]

In 1919, Alexander McLean Nicolson worked with Rochelle salt developing audio related inventions like microphones and speakers at Bell Labs. [10]

Related Research Articles

<span class="mw-page-title-main">Piezoelectricity</span> Electric charge generated in certain solids due to mechanical stress

Piezoelectricity is the electric charge that accumulates in certain solid materials—such as crystals, certain ceramics, and biological matter such as bone, DNA, and various proteins—in response to applied mechanical stress. The word piezoelectricity means electricity resulting from pressure and latent heat. It is derived from Ancient Greek πιέζω (piézō) 'to squeeze or press', and ἤλεκτρον (ḗlektron) 'amber'. The German form of the word (Piezoelektricität) was coined in 1881 by the German physicist Wilhelm Gottlieb Hankel; the English word was coined in 1883.

<span class="mw-page-title-main">Potassium ferrocyanide</span> Chemical compound

Potassium hexacyanidoferrate(II) is the inorganic compound with formula K4[Fe(CN)6]·3H2O. It is the potassium salt of the coordination complex [Fe(CN)6]4−. This salt forms lemon-yellow monoclinic crystals.

<span class="mw-page-title-main">Tartaric acid</span> Organic acid found in many fruits

Tartaric acid is a white, crystalline organic acid that occurs naturally in many fruits, most notably in grapes but also in tamarinds, bananas, avocados, and citrus. Its salt, potassium bitartrate, commonly known as cream of tartar, develops naturally in the process of fermentation. Potassium bitartrate is commonly mixed with sodium bicarbonate and is sold as baking powder used as a leavening agent in food preparation. The acid itself is added to foods as an antioxidant E334 and to impart its distinctive sour taste. Naturally occurring tartaric acid is a useful raw material in organic chemical synthesis. Tartaric acid, an alpha-hydroxy-carboxylic acid, is diprotic and aldaric in acid characteristics and is a dihydroxyl derivative of succinic acid.

<span class="mw-page-title-main">Potassium chloride</span> Ionic compound (KCl)

Potassium chloride is a metal halide salt composed of potassium and chlorine. It is odorless and has a white or colorless vitreous crystal appearance. The solid dissolves readily in water, and its solutions have a salt-like taste. Potassium chloride can be obtained from ancient dried lake deposits. KCl is used as a fertilizer, in medicine, in scientific applications, domestic water softeners, and in food processing, where it may be known as E number additive E508.

<span class="mw-page-title-main">Potassium tartrate</span> Chemical compound

Potassium tartrate, dipotassium tartrate or argol has formula K2C4H4O6. It is the potassium salt of tartaric acid. It is often confused with potassium bitartrate, also known as cream of tartar. As a food additive, it shares the E number E336 with potassium bitartrate.

<span class="mw-page-title-main">Potassium hydroxide</span> Inorganic compound (KOH)

Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash.

<span class="mw-page-title-main">Potassium bicarbonate</span> Chemical compound

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.

<span class="mw-page-title-main">Potassium chlorate</span> Chemical compound

Potassium chlorate is a compound containing potassium, chlorine and oxygen, with the molecular formula KClO3. In its pure form, it is a white crystalline substance. After sodium chlorate, it is the second most common chlorate in industrial use. It is a strong oxidizing agent and its most important application is in safety matches. In other applications it is mostly obsolete and has been replaced by safer alternatives in recent decades. It has been used

<span class="mw-page-title-main">Polyvinylidene fluoride</span> Non-reactive thermoplastic fluoropolymer

Polyvinylidene fluoride or polyvinylidene difluoride (PVDF) is a highly non-reactive thermoplastic fluoropolymer produced by the polymerization of vinylidene difluoride. Its chemical formula is (C2H2F2)n.

<span class="mw-page-title-main">Fehling's solution</span> Chemical test for the reducibility of a sugar

In organic chemistry, Fehling's solution is a chemical reagent used to differentiate between water-soluble carbohydrate and ketone functional groups, and as a test for reducing sugars and non-reducing sugars, supplementary to the Tollens' reagent test. The test was developed by German chemist Hermann von Fehling in 1849.

<span class="mw-page-title-main">Potassium bitartrate</span> Chemical salt used in cooking as cream of tartar

Potassium bitartrate, also known as potassium hydrogen tartrate, with formula KC4H5O6, is a chemical compound with a number of uses. It is the potassium acid salt of tartaric acid (a carboxylic acid). In cooking, it is known as cream of tartar.

<span class="mw-page-title-main">Caesium fluoride</span> Chemical compound

Caesium fluoride or cesium fluoride is an inorganic compound with the formula CsF. A hygroscopic white salt, caesium fluoride is used in the synthesis of organic compounds as a source of the fluoride anion. The compound is noteworthy from the pedagogical perspective as caesium also has the highest electropositivity of all commonly available elements and fluorine has the highest electronegativity.

<span class="mw-page-title-main">Sodium iodide</span> Chemical compound

Sodium iodide (chemical formula NaI) is an ionic compound formed from the chemical reaction of sodium metal and iodine. Under standard conditions, it is a white, water-soluble solid comprising a 1:1 mix of sodium cations (Na+) and iodide anions (I) in a crystal lattice. It is used mainly as a nutritional supplement and in organic chemistry. It is produced industrially as the salt formed when acidic iodides react with sodium hydroxide. It is a chaotropic salt.

<span class="mw-page-title-main">Sodium dithionite</span> Chemical compound

Sodium dithionite is a white crystalline powder with a sulfurous odor. Although it is stable in dry air, it decomposes in hot water and in acid solutions.

<span class="mw-page-title-main">Tartrate</span> Chemical compound

A tartrate is a salt or ester of the organic compound tartaric acid, a dicarboxylic acid. The formula of the tartrate dianion is OOC-CH(OH)-CH(OH)-COO or C4H4O62−.

Chiral resolution, or enantiomeric resolution, is a process in stereochemistry for the separation of racemic mixture into their enantiomers. It is an important tool in the production of optically active compounds, including drugs. Another term with the same meaning is optical resolution.

The Lemieux–Johnson or Malaprade–Lemieux–Johnson oxidation is a chemical reaction in which an olefin undergoes oxidative cleavage to form two aldehyde or ketone units. The reaction is named after its inventors, Raymond Urgel Lemieux and William Summer Johnson, who published it in 1956. The reaction proceeds in a two step manner, beginning with dihydroxylation of the alkene by osmium tetroxide, followed by a Malaprade reaction to cleave the diol using periodate. Excess periodate is used to regenerate the osmium tetroxide, allowing it to be used in catalytic amounts. The Lemieux–Johnson reaction ceases at the aldehyde stage of oxidation and therefore produces the same results as ozonolysis.

<span class="mw-page-title-main">Ammonium dihydrogen phosphate</span> Chemical compound

Ammonium dihydrogen phosphate (ADP), also known as monoammonium phosphate (MAP) is a chemical compound with the chemical formula (NH4)(H2PO4). ADP is a major ingredient of agricultural fertilizers and dry chemical fire extinguishers. It also has significant uses in optics and electronics.

<span class="mw-page-title-main">Monosodium tartrate</span> Chemical compound

Monosodium tartrate or sodium bitartrate is a sodium acid salt of tartaric acid. As a food additive it is used as an acidity regulator and is known by the E number E335. As an analytical reagent, it can be used in a test for ammonium cation which gives a white precipitate.

<span class="mw-page-title-main">Sodium ammonium tartrate</span> Chemical compound

Sodium ammonium tartrate (NAT) is an organic compound with the formula Na(NH4)[O2CCH(OH)CH(OH)CO2]. The salt is derived from tartaric acid by neutralizing with ammonia and with sodium hydroxide. Louis Pasteur obtained enantiopure crystals of the tetrahydrate of NAT, via the process of spontaneous resolution. His discovery led to increased study of optical activity, which eventually was shown to have broad implications. Many modification of this salt have been investigated by X-ray crystallography, including the racemate, which crystallizes as the monohydrate.

References

  1. David R. Lide, ed. (2010), CRC Handbook of Chemistry and Physics (90th ed.), CRC Press, pp. 4–83
  2. 1 2 3 Jean-Maurice Kassaian (2007), "Tartaric Acid", Ullmann's Encyclopedia of Industrial Chemistry (7th ed.), Wiley, pp. 1–8, doi:10.1002/14356007.a26_163, ISBN   978-3-527-30385-4
  3. Newnham, R.E.; Cross, L. Eric (November 2005). "Ferroelectricity: The Foundation of a Field from Form to Function". MRS Bulletin. 30 (11): 845–846. doi:10.1557/mrs2005.272. S2CID   137948237.
  4. Fieser, L. F.; Fieser, M., Reagents for Organic Synthesis; Vol.1; Wiley: New York; 1967, p. 983
  5. "Rochelle Salt applications".
  6. Summerlin, L. B. (January 1977). "SP-401 Skylab, Classroom in Space". NASA. Retrieved 2009-06-06.
  7. Electronic Engineering, March, 1951.
  8. "A Short History of Ferroelectricity" (PDF). groups.ist.utl.pt. 2009-12-04. Retrieved 2016-05-04.
  9. Brewster, David (1824). "Observations of the pyro-electricity of minerals". The Edinburgh Journal of Science. 1: 208–215.
  10. url = https://sites.google.com/view/rochellesalt/home