Sodium tartrate

Structural formula
L - (+) - disodium tartrate
General
Surname	Sodium tartrate
other names	L -tartaric acid disodium salt E  335
Molecular formula	C 4 H 4 Na 2 O 6
Brief description	colorless rhombic crystals (dihydrate)
External identifiers / databases
CAS number 51307-92-7 (racemate) PubChem 13355 ChemSpider 12786 Wikidata Q283499
Drug information
ATC code	A06 AD21
properties
Molar mass	194.08 g · mol -1
Physical state	firmly
density	1.81 g cm −3 (dihydrate)
Melting point	150 ° C (dihydrate)
solubility	good in water (330 g l −1 at 25 ° C for L - (+) - disodium tartrate)
safety instructions
Please note the exemption from the labeling requirement for drugs, medical devices, cosmetics, food and animal feed GHS labeling of hazardous substances no GHS pictograms H and P phrases H: no H-phrases P: no P-phrases
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Sodium tartrate is a sodium salt of tartaric acid with the empirical formula C ₄ H ₄ O ₆ Na ₂ . It occurs in a bound form in many fruits.

Isomers

Like tartaric acid, sodium tartrate also has two stereocenters . Depending on the configuration of these centers, D - (-) - sodium tartrate [synonym: ( 2S , 3S ) -sodium tartrate ], L - (+) - sodium tartrate [synonym: ( 2R , 3R ) -sodium tartrate ] or the optically inactive meso - Sodium tartrate. In the meso form, one of the stereocenters is ( R ) - the other ( S ) -configured . "Sodium tartrate" without a specific name mostly refers to L - (+) - sodium tartrate.

Isomers of sodium tartrate
Surname	L - (+) - sodium tartrate	D - (-) - sodium tartrate	meso sodium tartrate
Structural formula
other names	(2 R , 3 R ) -tartaric acid disodium salt	Disodium salt of (2 S , 3 S ) -tartaric acid	Disodium salt of meso -tartaric acid Disodium salt of (2 R , 3 S ) -tartaric acid (2 S , 3 R ) -tartaric acid disodium salt
CAS number	868-18-8 (anhydrate) 6106-24-7 (dihydrate)	109175-69-1 (anhydrate) 22476-07-9 (dihydrate)	4504-50-1
	51307-92-7 ( racemate )
	? (Mixture of isomers)
EC number	212-773-3 (anhydrate) 612-074-7 (dihydrate)	244-213-9 (anhydrate)	224-817-9
ECHA info card	100.011.613 (anhydrate) 100.122.993 (dihydrate)	100.040.179 (anhydrate)	100.022.563
PubChem	162637 (anhydrate) 12598458 (dihydrate)	159905 (anhydrate)	165240
	13355 (mixture of isomers)
Wikidata	Q27132338 (anhydrate) Q27276410 (dihydrate)	Q27282569 (anhydrate)	Q27266651
	Q283499 (mixture of isomers)

Presentation and extraction

Sodium tartrate is usually made from natural tartaric acid, which in turn is obtained from tartar from wine residues, which is first mixed with milk of lime and then with sulfuric acid .

use

Sodium tartrate dihydrate

Since a defined amount of water of crystallization is bound in crystalline sodium tartrate , it is a common primary standard for the Karl Fischer method , a widely used method for the quantitative determination of water by titration.

Sodium tartrate and sodium hydrogen tartrate from (natural) L - (+) - tartaric acid are used as leavening agents , as acidulants or acid regulators, and also as a substitute for table salt . Due to the property of tartrates to form stable complexes with iron and heavy metal ions, they support the effect of antioxidants and are therefore also used as complexing agents. It is approved in the EU as a food additive with the number E 335 with a permitted daily dose of 30 mg per kilogram of body weight and is then considered to be harmless.

Individual evidence

1. ↑ Entry on E 335: Sodium tartrates in the European database for food additives, accessed on June 27, 2020.
2. ↑ ^{a b c} Entry on sodium tartrate. In: Römpp Online . Georg Thieme Verlag, accessed on April 26, 2018.
3. ↑ George WA Milne: Drugs: Definitions and Properties Definitions and Properties . Routledge, 2018, ISBN 978-1-351-78989-9 ( limited preview in Google Book Search).
4. ↑ ^{a b} Sodium L-tartrate dibasic dihydrate data sheet from Sigma-Aldrich , accessed on April 26, 2018 ( PDF ).