They are precipitated from their alkaline solutions as cobalt sulphide by sulphuretted hydrogen, but this precipitation is prevented by the presence of citric and tartaric acids; similarly the presence of ammonium salts hinders their precipitation by caustic alkalis.
He recommended that yeast should be purified by cultivating it in a solution of sugar containing tartaric acid, or, in wort containing a small quantity of phenol.
Berzelius by the dry distillation of tartaric or racemic acids (Pogg.
It is usually made by distilling tartaric acid with potassium bisulphate at about zoo-250° C., the crude product being afterwards fractionated.
This base is resolved into its active components by d-tartaric acid, l-nicotine-d-tartrate crystallizing out first.
In alkaline solution, potassium permanganate oxidizes it to inactive tartaric acid and carbon dioxide (0.
It was that of two tartaric acids, deposited from wine-lees.
The impurities occasionally present in commercial citric acid are salts of potassium and sodium, traces of iron, lead and copper derived from the vessels used for its evaporation and crystallization, and free sulphuric, tartaric and even oxalic acid.
Tartaric acid, which is sometimes present in large quantities as an adulterant in commercial citric acid, may be detected in the presence of the latter, by the production of a precipitate of acid potassium tartrate when potassium acetate is added to a cold solution.
Citric acid is also distinguished from tartaric acid by the fact that an ammonia solution of silver tartrate produces a brilliant silver mirror when boiled, whereas silver citrate is reduced only after prolonged ebullition.
Doebner's preparation of mesotartaric acid, the internally compensated tartaric acid, (CH(OH) COOH)21 by oxidizing phenol with dilute potassium permanganate (Ber., 1891,.
Kekule (Ann., 1883, 221, p. 230), however, reinvestigated this acid; he showed that it was dibasic and not tribasic; that it gave tartaric acid on reduction; and, finally, that it was dioxytartaric acid, HOOC C(OH) 2 C(OH) 2 COOH.
The identity of the formulae and osazones of d-mannose and d-glucose showed that the stereochemical differences were situated at the carbon atom adjacent to the aldehyde group. Fischer applied a method indicated by Pasteur in converting dextro into laevo-tartaric acid; he found that both d-mannonic and d-gluconic acids (the latter is yielded by glucose on oxidation) were mutually convertible by heating with quinoline under pressure at 140°.
When heated to about 200° it yields a brown amorphous substance, named caramel, used in colouring liquors, &c. Concentrated sulphuric acid gives a black carbonaceous mass; boiling nitric acid oxidizes it to d-saccharic, tartaric and oxalic acids; and when heated to 160° with acetic anhydride an octa-acetyl ester is produced.
It may be prepared by heating racemic acid (see TARTARIC Acid) with fuming hydriodic acid; by heating fumaric acid (q.v.) with water at 150-200° C.; by the action of nitrous acid on inactive aspartic acid; and by the action of moist silver oxide on monobromsuccinic acid.
Graham's work was developed by Liebig, who called into service many organic acids - citric, tartaric, cyanuric, comenic and meconic - and showed that these resembled phosphoric acid; and he established as the criterion of polybasicity the existence of compound salts with different metallic oxides.
Traces of bismuth may be detected by treating the solution with excess of tartaric acid, potash and stannous chloride, a precipitate or dark coloration of bismuth oxide being formed even when only one part of bismuth is present in 20,000 of water.
(5) Sodii citro-tartras effervescens, a mixture of sugar, sodium bicarbonate, citric and tartaric acids.
While there he wrote an account of his experiments with cream of tartar, from which he had isolated tartaric acid, and sent it to T.
Such bases occur almost exclusively in the dicotyledons, generally in combination with malic, citric, tartaric or similar plant-acids.
In many cases it is found that hydrogen peroxide will only act as an oxidant when in the presence of a catalyst; for example, formic, glygollic, lactic, tartaric, malic, benzoic and other organic acids are readily oxidized in the presence of ferrous sulphate (H.
This latter reaction is hindered by the presence of many organic acids (tartaric acid, citric acid, &c.).
Synthetically it may ba obtained by reducing malic or tartaric acids with hydriodic acid (R.
CH (CH 3) C02H, is formed by the dry distillation of tartaric acid; by heating pyruvic acid with concentrated hydrochloric acid to 180° C.; by the reduction of citraconic and mesaconic acids with sodium amalgam; and by the hydrolysis of /-cyanbutyric acid.
At the beginning of July when the berries have attained to an appreciable size - the specific gravity of the juice is very low; it contains very little sugar, but a good deal of acid, chiefly free tartaric acid and malic acid.
The character of the acidity, however, changes, the free tartaric acid gradually disappearing, forming bitartrate of potash and being otherwise broken up. On the other hand, the free malic acid increases and the tannin decreases.
This reduction of acidity is partly due to the deposition of various salts of tartaric acid, which are less soluble in a dilute alcoholic medium than in water, and partly to the action of micro-organisms. Young wines differ very widely in their composition according to class and vintage.
It has been found, for instance, that in the case of the mannitic disease the action of the micro-organism may be checked, or prevented altogether, by bringing the acidity of the must up to a certain level by the addition of a small quantity of tartaric acid.
In repeating and extending the experiments of Haiiy much later, Sir David Brewster discovered that various artificial salts were pyro-electric, and he mentions the tartrates of potash and soda and tartaric acid as exhibiting this property in a very strong degree.
TARTARIC ACID (dihydroxy-succinic acid), C 4 H 6 0 6, or HO 2 C CH (OH) CH (OH) CO 2 H.
Four acids of this composition are known, namely dextroand laevo-tartaric acids, racemic acid and mesotartaric acid, the two last being optically inactive (see Stereo-Isomerism).
Dextro-tartaric acid occurs in the free state or as the potassium or calcium salt in grape juice and in various unripe fruits.
Laevo-tartaric acid is identical in its chemical and in most of its physical properties with the dextro-acid, differing chiefly in its action on polarized light, the plane of polarization being rotated to the left.
Pasteur, Ann., 1853, 88, p. 212); by heating tartaric or racemic acid for some time with water to 165° C.; by the oxidation of laevulose; and by the oxidation of phenol or maleic acid with an alkaline solution of potassium permanganate (0.
Tartaric acid as used in medicine is derived from potassium acid tartrate.
Tartaric acid is rarely used alone, but is contained in pilula quininae sulphatis and in Seidlitz powder (see Sodium), and is a constituent of many proprietary granular effervescent preparations.
If taken in overdose or in a concentrated form tartaric acid produces severe gastro-enteritis.
It is a white powder, almost insoluble in water, and when volatilized, condenses in two crystalline forms, either octahedral or prismatic. It is insoluble in sulphuric and nitric acids, but is readily soluble in hydrochloric and tartaric acids and in solutions of the caustic alkalies.
The corresponding hydroxide, orthoantimonious acid, Sb(OH) 31 can be obtained in a somewhat impure form by precipitating tartar emetic with dilute sulphuric acid; or bet::er by decomposing antimonyl tartaric acid with sulphuric acid and drying the precipitated white powder at too° C. Antimony tetroxide is formed by strongly heating either the trioxide or pentoxide.