Potassium tartrates

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. 

Description of Method. Salt substitutes, which are used in place of table salt for individuals on a low-sodium diet, contain KCI. Depending on the brand, fumaric acid, calcium hydrogen phosphate, or potassium tartrate also may be present. Typically, the concentration of sodium in a salt substitute is about 100 ppm. The concentration of sodium is easily determined by flame atomic emission. Because it is difficult to match the matrix of the standards to that of the sample, the analysis is accomplished by the method of standard additions. 

Fig. 4. Manufacturing process for (R-R, R -tartaric acid (TA) and its salts, calcium tartrate (CT) and potassium tartrate (PT).

For the production of tartar emetic (antimony potassium tartrate [28300-74-5]), potassium bitartrate [868-14 ] and antimony oxide, Sb202, are added simultaneously to water in a stainless-steel reactor. The reaction mixture is diluted, filtered, and collected in jacketed granulators where crystallization takes place after cooling. Centrihiging, washing, and drying complete the process. 

Approximately 98% of the potassium recovered ia primary ore and natural brine refining operations is recovered as potassium chloride. The remaining 2% consists of potassium recovered from a variety of sources. Potassium produced from these sources occurs as potassium sulfate combiaed with magnesium sulfate. Prom a practical point of view, the basic raw material for ak of the potassium compounds discussed ia this article, except potassium tartrate, is potassium chloride. Physical properties of selected potassium compounds are Hsted ia Table 3, solubkities ia Table 4. 

Complexing agents, which act as buffers to help control the pH and maintain control over the free metal—salt ions available to the solution and hence the ion concentration, include citric acid, sodium citrate, and sodium acetate potassium tartrate ammonium chloride. Stabilizers, which act as catalytic inhibitors that retard the spontaneous decomposition of the bath, include fluoride compounds thiourea, sodium cyanide, and urea. Stabilizers are typically not present in amounts exceeding 10 ppm. The pH of the bath is adjusted. 

Antimony potassium tartrate (tartar emetic) has the advantage of being low in cost. It has been called the dmg of choice for Schistosoma japonicum infection (204) even though it fails to cure the disease in many patients. However, trivalent antimonials are no longer recommended for the treatment of helminthic infections because these compounds have an unacceptable toxicity and are too difficult to administer (205). 

Antimony compounds have been used to treat leishmaniasis ever since tartar emetic (antimony potassium tartrate) was discovered early in the 20th century to have efficacy against the mucocutaneous form of the disease. The cutaneous form has been treated with tartar emetic formulated in an ointment. Many side effects have been seen with this trivalent antimonial, some of which can be ascribed to the difficulty of obtaining pure antimony for its manufacture. These side effects include toxicity to the heart, Hver, and kidneys. Other promising trivalent antimonials have been abandoned in favor of pentavalent antimonials with lower toxicity. 

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. 

Archer, owing to very unfortunate coincidences, had mistaken acid potassium tartrate for the acetylamino acid. Goldfarb et al. prepared authentic 5-acetylamino-2-thiophenecarboxylic acid, mp 230 232°C (methyl ester, mp 171-171.5°C ethyl ester, mp 161°C), through reduction of 5-nitro-2-thiophenecarboxylic acid with Raney nickel in acetic anhydride and proved the structure by Raney nickel desulfurization to 8-aminovaleric acid. They also confirmed that the acid mp 272-273°C (methyl ester, mp 135-136°C ethyl ester, mp 116-117°C) is 4-acetylamino-2-thiophenecar boxy lie acid as originally stated by Steinkopf and Miiller. The statement of Tirouflet and Chane that the acid obtained upon reduction and acetylation of 5-nitro-2-thiophenecarboxylic acid melts at 272°C must result from some mistake as they give the correct melting point for the methyl ester. 

Eisen-wasser, n. chalybeate water, -wein, m. Pharm.) iron wine, -weinstein, m. Pharm.) iron and potassium tartrate, tartrated iron, -werk, n. ironworks, iron mill, -wolfram, n. ferrotungsten. -zeit, /. iron age. -zement, m. n. ferroconcrete, -zinkblende, /. mar-matite. -zinkspat, m. ferruginous calamine, -zinnerz, n. ferriferous cassiterite. -zucker, m. Pharm.) saccharated ferric oxide, -zuk-kersinip, m. Pharm.) sirup of ferric oxide. 

Kaiium, n. potassium, -alatm, m. potassium alum, -azetat, n. potassium acetate, -bor-fluorid, n. potassium fluoborate. -brech-weinstein, m. antimonyl potassium tartrate, tartar emetic. 

Rochellesalz, n. Rochelle salt, sodium potassium tartrate. 

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