Potassium-sodium tartrate

Fehling s solution A solution of copper sulphate, sodium potassium tartrate and NaOH used for estimating and detecting reducing sugars. 

Tartaric acid is noteworthy for a) the excellent way in which the majority of its salts Crystallise, and h) the frequent occurrence of salts having mixed cations. Examples of the latter are sodium potassium tartrate (or Rochelle salt), C4H40 NaK, used for the preparation of Fehling s solution (p. 525), sodium ammonium tartrate, C4H OaNaNH4, used by Pasteur for his early optical resolution experiments, and potassium antimonyl tartrate (or Tartar Emetic), C4H404K(Sb0). The latter is prepared by boiling a solution of potassium hydrogen tartrate (or cream of tartar ) with antimony trioxide,... 

Solution B. Dissolve 86 5 g. of crystalline sodium potassium tartrate ( Rochelle salt, C4H40jNaK,4H20) in warm water. Dissolve 30 g. of pure sodium hydroxide in water. Mix the tartrate and hydroxide solutions, cool and make up to 250 ml. in a graduated flask. 

Solution B. Dissolve 346 g. of sodium potassium tartrate (C4H40gNaK,4H20, Rochelle salt ) and 120 g. of NaOH in water and make the mixed tartrate and hydroxide solution up to i litre. 

Solution No. 2. Dissolve 60 g. of pure sodium hydroxide and 173 g. of pure Rochelle salt (sodium potassium tartrate) in water, filter if necessary through a sintered glass funnel, and make up the filtrate and washings to 500 ml. 

The ethereal solution of crude quinidine and cinchonidine, obtained as described under cinchonine, is shaken with dilute hydrochloric acid, the excess acid neutralised with ammonia and sodium potassium tartrate added. The base is recovered from the precipitated tartrate by dissolving the latter in dilute acid and pouring the filtered solution in a thin stream, slowly and with constant stirring, into excess of ammonia solution. The crude alkaloid is converted into the neutral sulphate, and this recrystallised... 

Koppeschaar), is a crystalline precipitate, sparingly soluble in water (1 in 1,265 at 10°), almost insoluble in sodium potassium tartrate solution, and is the form in which the alkaloid is usually estimated. 

In many cases separation of the aluminum salts and cyclohexanone cannot be carried out as in the above experiment. In these cases the aluminum salts can generally be removed by washing with dilute hydrochloric acid or with aqueous Rochelle salt (sodium potassium tartrate) solution. Cyclohexanone and cyclohexanol can be conveniently removed by steam distillation as described in the following experiment. 

Rochellesalz, n. Rochelle salt, sodium potassium tartrate. 

After stirring at room temperature for 20 minutes, the reaction mixture was cooled to 0 °C and transferred via a cannula into saturated aqueous NaHCC>3 (15mL). Saturated aqueous sodium potassium tartrate was added (15mL). 

The reaction of Rochelles salt, sodium potassium tartrate, with hydrogen peroxide is catalyzed with C0CI2 at 70°C. Photograph A shows the reactants before mixing. 

Fehling s reagent analychem A solution of cupric sulfate, sodium potassium tartrate, and sodium hydroxide, used to test for the presence of reducing compounds such as sugars. fal-iijz re,a-j3nt ... 

Pauling scale phys chem A numerical scale of electronegativities based on bond-energy calculations for different elements joined by covalent bonds. pol-iri Skal Pavy s solution analychem Laboratory reagent used to determine the concentration of sugars in solution by color titration contains copper sulfate, sodium potassium tartrate, sodium hydroxide, and ammonia in water solution. pa-vez S3,lu-sh3n Pb See lead. 

Phenylisopropyl-hydroxylamine can be reduced to phenylisopropylamine as follows A solution of 6g (0.04 mole) of phenylisopropyl-hydroxylamine in 80 ml of absolute ether is treated with 1.9 g (0.05 mole) of LAH in 150 ml of absolute ether in the usual manner and refluxed for an additional hour. After cooling, a sample of the reaction mixture should give a positive Gilman-Shulze color test, indicating an excess of the hydride (this test is not necessary for you to perform). Hydrolysis was carried out with 400 ml of 20% aqueous sodium potassium tartrate and after separation of the layers, the aqueous portion is extracted with two additional 75 ml volumes of ether. Rectification yields 2.0 g of substituted phenylisopropylamine. JACS, 1837 (1952). 

Isolation of the products is accomplished by decomposition with sodium potassium tartrate [576], by water and dilute sodium hydroxide [727], or by successive treatment with 6n sulfuric acid followed by alkalization with potassium hydroxide [787]. 

D. Tris[(2-peiiluorohexyl)ethyl]tin hydride (Note 7). A 1-L, three-necked flask and a stirring bar are dried in an oven. The fluorous tin bromide (13.8 g, 11.1 mmol) is dissolved in dry ether (275 mL) and transferred to the dried three-necked flask equipped with a thermometer, stirring bar, and an outlet to argon. The solution is cooled to O C. AIM solution of iithium aluminum hydride (LAH) in ether (11.1 mL, 11.1 mmol) is added dropwise over 45 min to the solution. The addition rate is adjusted to maintain a temperature between 0° and 1°C. The reaction mixture is stirred for 6 hr at 0°C. Water (75 mL) is slowly added (initially dropwise) with stirring to the ice-cold mixture. Sodium potassium tartrate (20%) (250 mL) is added and the mixture is transferred to a 1-L separatory funnel. The ethereal layer is separated and the aqueous layer is extracted three times with ether (3 x 100 mL). The combined extracts are dried with magnesium sulfate and vacuum filtered into a 1-L, round-bottomed flask. The solvent is evaporated under reduced pressure. The cmde product is distilled under a reduced pressure of 0.02 mm at 133-140°C to provide 11.3 g (9.69 mmol, 87%) of the pure product as an oil (Notes 8 and 9). 

Lactose is a reducing sugar, i.e. it is capable of reducing appropriate oxidizing agents, two of which are usually used, i.e. alkaline copper sulphate (CuS04 in sodium potassium tartrate Fehling s solution) or chloroamine-T (2.1). 

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