On boiling their solution in caustic alkalis, ammonia is liberated.
Uracil and its homologues may be obtained in many cases from the hydrouracils by the action of bromine, and subsequent elimination of the elements of hydrobromic acid; or by the condensation of aceto-acetic ester and related substances with urea, thiourea, guanidine, &c. Uracil, C4H402N2, crystallizes in colourless needles, is soluble in hot water and melts with decomposition at 335° C. Hydrouracil, C4H602N2, is obtained by the action of bromine and caustic alkalis on succinamide (H.
The powder is soluble in alcohol and strong solutions of alkalis, such as ammonia.
Alkalis decompose it into picro-podophyllic acid and picro-podophyllin, minute traces of both of which occur in a free state in the rhizome.
It is a liquid which boils at 93° C. and with caustic alkalis polymerizes to diacetyldicyanide.
Ethylene dibromide) with silver acetate or with potassium acetate and alcohol, the esters so produced being then hydrolysed with caustic alkalis, thus: C 2 H 4 Br 2 + C2H302 Ag-*C2H4(O C2H30)2->C2H4(OH)2+2K C2H302 by the direct union of water with the alkylen oxides; by oxidation of the olefines with cold potassium permanganate solution (G.
This precipitate is insoluble in cold dilute acids, in ammonium sulphide, and in solutions of the caustic alkalis," a behaviour which distinguishes it from the yellow sulphides of arsenic and tin.
Lime) were found to be very similar in properties to those of the alkalis, they were called alkaline earths.
It is also readily soluble in solutions of the caustic alkalis, slightly soluble in aqueous ammonia solution, and almost insoluble in sodium carbonate solution.
They are not decomposed by boiling alkalis, but on heating with hydriodic acid they split into their components.
Alkalis which form soluble carbolates are useless.
It is appreciably soluble in water, and also in solutions of the caustic alkalis and alkaline sulphides.
It is obtainable from most natural fatty bodies by the action of alkalis and similar reagents, whereby the fats are decomposed, water being taken up, and glycerin being formed together with the alkaline salt of some particular acid (varying with the nature of the fat).
Owing to their possession of this common property, these natural fatty bodies and various artificial derivatives of glycerin, which behave in the same way when treated with alkalis, are known as glycerides.
The simplest modes of preparing pure glycerin are based on the saponification of fats, either by alkalis or by superheated steam, and on the circumstance that, although glycerin cannot be distilled by itself under the ordinary pressure without decomposition, it can be readily volatilized in a current of superheated steam.
In its medicinal use glycerin is an excellent solvent for such substances as iodine, alkaloids, alkalis, &c., and is therefore used for applying them to diseased surfaces, especially as it aids in their absorption.
It may also be obtained by oxidizing allylene and propylene with cold potassium permanganate solution, by the hydrolysis of barbituric acid (malonyl urea) with alkalis (A.
Iron and quinine citrate is used as a bitter stomachic and tonic. In the blood citrates are oxidized into carbonates; they therefore act as remote alkalis, increasing the alkalinity of the blood and thereby the general rate of chemical change within the body.
The alkalis are used almost exclusively in the condition of caustic lyessolutions of their respective hydrates in water.
The process of manufacturing soaps by boiling fatty acids with caustic alkalis or sodium carbonate came into practice with the development of the manufacture of candles by saponifying fats, for it provided a means whereby the oleic acid, which is valueless for candle making, could be worked up. The combination is effected in open vats heated by a steam coil and provided with a stirring appliance; if soda ash be used it is necessary to guard against boiling over.
Toilet soaps of common quality are perfumed by simple melting and stirring into the mass some cheap odorous body that is not affected by alkalis under the influence of heat.
With genuine soaps, however, it suffices to calculate the fatty acids as anhydrides and add to this the amount of alkalis, and estimate the water by difference.
The complete analysis involves an examination of the fatty matter, of the various forms in which the alkalis are present - free and combined glycerin, &c.
They first invented and named the alembic for the purposes of distillation, analyzed the substances of the three kingdoms of nature, tried the distinction and affinities of alkalis and acids, and converted the poisonous minerals into soft and salutary remedies.
By the action of aqueous alkalis, carbon bisulphide is converted into a mixture of an alkaline carbonate and an alkaline thiocarbonate (J.
The per-ruthenate, KRuO 4, formed by the action of chlorine on the ruthenate, or of alkalis on the peroxide at 50° C., is a black crystalline solid which is stable in dry air but decomposes when heated strongly.
Berzelius's investigation of the action of the electric current on salts clearly demonstrated the invaluable assistance that electrolysis could render to the isolator of elements; and the adoption of this method by Sir Humphry Davy for the analysis of the hydrates of the metals of the alkalis and alkaline earths, and the results which he thus achieved, established its potency.
BdXXo, a green bud, on account of a brilliant green line in its spectrum) in the selenious mud of the sulphuric acid manufacture; the chemical affinities of this element, on the one hand approximating to the metals of the alkalis, and on the other hand to lead, were mainly established by C. A.
The heptachlor compound when treated with chlorine water gives trichloraceto-pentachlorbutyric acid (6), which is hydrolysed by alkalis to chloroform and pentachlorglutaric acid (7), and is converted by boiling water into tetrachlor-diketo-Rpentene (8).
This latter compound may be chlorinated to perchloracetoacrylic chloride (9), from which the corresponding acid (to) is obtained by treatment with water; alkalis hydrolyse the acid to chloroform and dichlormaleic acid (I I).
HO NH SO 3 Na, are hydrolysed by caustic alkalis (E.
When heated with CS 2 to 1 00° C. under pressure, it forms liquid nitrogen sulphide, N 2 S 5, a mobile red liquid which solidifies to an iodine-like mass of crystals which melt at Io-I I° C. Water, alkalis and acids decompose it into sulphur and ammonia (W.
On fusion with caustic alkalis they decompose into their constituent aminothiophenol and acid.
During the earliest investigation of the subject it was thought that, since hydrogen and oxygen were usually evolved, the electrolysis of solutions of acids and alkalis was to be regarded as a direct decomposition of water.
3 The colour changes shown by many substances which are used as indicators of acids or alkalis can be explained in a similar way.
Alkalis partially convert it into d-mannose and d-fructose.
Alkalis have little effect on it under ordinary circumstances, although prolonged contact with ammonia results in a partial change.
They are silicates, usually orthosilicates, of aluminium together with alkalis (potassium, sodium, lithium, rarely rubidium and caesium), basic hydrogen, and, in some species magnesium, ferrous and ferric iron, rarely chromium, manganese and barium.
Clarke (1889-1893) supposes them to be substitution derivatives of normal aluminium orthosilicate A14(S104)3, in which part of the aluminium is replaced by alkalis, magnesium, iron and the univalent groups (MgF), (A1F2),(AlO), (MgOH); an excess of silica is explained by the isomorphous replacement of H 4 SiO 4 by the acid H4S130s.
Winckler, Ann., 1836, 18, 3 10), by boiling phenylchloracetic acid with alkalis (A.
By the action of alkalis it is converted into iso-eugenol, which on oxidation yields vanillin, the odorous principle of vanilla.
It crystallizes in rhombic prisms which are readily soluble in hot water, melt at 187° C. and decompose at about 240° C. It is readily hydrolysed by hot caustic alkalis to benzoic acid and glycocoll.
Alcoholic solutions of the alkalis also produce much nitrite along with some formate and acetate.
The power of resisting the disintegrating effects of atmospheric moisture and carbonic acid, depends largely upon the quantity of alkalis contained in the glass and their proportion to the lead, lime or barium present, the stability being generally less the higher the proportion of alkali.
They show all the reactions of esters, being readily hydrolysed by caustic alkalis, and reacting with ammonia to produce carhamic esters and urea.
There is hardly a single metal which holds out against the alkalis themselves when in the state of fiery fusion; even platinum is most violently attacked.
Iron, which stands so well against aqueous alkalis, is most violently attacked by the fused reagents.
It forms crystalline needles soluble in alkalis, chloroform and Zoo parts of water.
Of the ketoses, we notice d-sorbose, found in the berries of mountain-ash, and d-tagatose, obtained by Lobry de Bruyn and van Ekenstein on treating galactose with dilute alkalis, talose and l-sorbose being formed at the same time.
It also dissolves in aqueous caustic alkalis, including ammonia, forming "zincates" [e.g.