noun
definition
An alkaline battery.
adjective
definition
Of, or relating to an alkali, one of a class of caustic bases.
definition
Having a pH greater than 7.
Examples of alkaline in a Sentence
Soaps give an alkaline reaction and have a decided acrid taste; in a pure condition - a state never reached in practice - they have neither smell nor colour.
It forms double chlorides with the alkaline chlorides.
The oxides of type RO are soluble in water, the solution possessing a strongly alkaline reaction and rapidly absorbing carbon dioxide on exposure; they are basic in character and dissolve readily in acids with the formation of the corresponding salts.
Acids have practically no action on the metal, but it is soluble in solutions of the alkaline hypochlorites.
Germanium compounds on fusion with alkaline carbonates and sulphur form salts known as thiogermanates.
Its property of absorbing large proportions of water, up to 80%, and yet present the appearance of a hard solid body, makes the material a basis for the hydrated soaps, smooth and marbled, in which water, sulphate of soda, and other alkaline solutions, soluble silicates, fuller's earth, starch, &c. play an important and bulky part.
Amongst the mineral springs worth mentioning are the sulphur springs at Ullersdorf, the saline ones at Luhatschowitz and the alkaline springs at TOplitz.
Ammonia, recognizable by its odour and alkaline reaction, indicates ammoniacal salts or cyanides containing water.
In this process cellulose (in the form of sawdust) is made into a stiff paste with a mixture of strong caustic potash and soda solution and heated in flat iron pans to 20o-250 C. The somewhat dark-coloured mass is lixiviated with a small amount of warm water in order to remove excess of alkali, the residual alkaline oxalates converted into insoluble calcium oxalate by boiling with milk of lime, the lime salt separated, and decomposed by means of sulphuric acid.
Potassium persulphate oxidizes it in alkaline solution, the product on boiling with acids giving hydroquiirone carboxylic acid (German Patent 81,297).
The springs are principally alkaline, alkaline and siliceous, acidic, or acidic and hepatic (sulphurous).
Ketoximes are usually rather more difficult to prepare than aldoximes, and generally require the presence of a fairly concentrated alkaline solution.
This may be effected by burning phosphorus in a confined volume of air, by the action of an alkaline solution of pyrogallol on air, by passing air over heated copper, or by the action of copper on air in the presence of ammoniacal solutions.
In acid solution, potassium permanganate oxidizes it to nitric acid, but in alkaline solution only to nitrous acid.
It is readily decomposed by water and alkaline hydroxides, yielding a mixture of nitrite and chloride.
That is, the concentration of H-ions decreases and that of the HO-ions increases; the water becomes more alkaline because the carbonic acid of the bicarbonate has been abstracted by the phytoplankton to the extent that normal carbonate is left.
Window glass exposed to alkaline vapours often shows a thin iridescent surface film which is supposed to be due to crystallization; the same change is found in pieces of Roman glass which have been dug out of the ruins of Pompeii.
He also found that the liquid round the anode became acid, and that round the cathode alkaline.
Barreswil found that a strongly alkaline solution of copper sulphate and potassium sodium tartrate (Rochelle salt) remained unchanged on boiling, but yielded an immediate precipitate of red cuprous oxide when a solution of glucose was added.
The latex exhibits a neutral, acid or alkaline reaction depending upon the plant from which it has been obtained.
In British Honduras an alkaline decoction prepared from the Moon plant (Calonictyon speciosum) is used for the same purpose.
Treatment with a warm alkaline solution is afterwards advisable, in order to remove traces of hydrochloric acid generated during the process.
Water when absolutely pure has no action on lead, but in the presence of air the lead is quickly attacked, with formation of the hydrate, Pb(OH) 2, which is appreciably soluble in water forming an alkaline liquid.
Plumbic acid, Pb0(OH) 21 is obtained as a bluish-black, lustrous body of electrolysing an alkaline solution of lead sodium tartrate.
It combines with alkaline chlorides - potassium, rubidium and caesium - to form crystalline plumbichlorides; it also forms a crystalline compound with quinoline.
Another process depends upon the formation of lead chloride by grinding together litharge with salt and water, and then treating the alkaline fluid with carbon dioxide until it is neutral.
An aqueous solution readily dissolves lead oxide, with formation of a strongly alkaline solution containing basic acetates (Acetum Plumbi or Saturni).
The hydrogen in the primary and secondary nitro compounds which is attached to the same carbon atom as the nitro group is readily replaced by bromine in alkaline solution.
In acid solution, amines are obtained, in alkaline solution, azoxy, azo and hydrazo compounds, and in neutral solution hydroxylamino compounds.
Cold mineral springs are at Bartfa, with alkaline ferruginous waters; Czigelka, with iodate waters; Parad, with ferruginous and sulphate springs; Koritnicza or Korytnica, with strong iron springs; and the mineral springs of Budapest.
It combines readily with alkaline and other chlorides to form double salts, e.g.
Stannic sulphide, SnS 2, is obtained by heating a mixture of tin (or, better, tin amalgam), sulphur and sal-ammoniac in proper proportions in the beautiful form of aurum musivum (mosaic gold) - a solid consisting of golden yellow, metallic lustrous scales, and used chiefly as a yellow "bronze" for plaster-of-Paris statuettes, &c. The yellow precipitate of stannic sulphide obtained by adding sulphuretted hydrogen to a stannic solution readily dissolves in solutions of the alkaline sulphides to form thiostannates of the formula M 2 SnS 31 the free acid, H2SnS3, may be obtained as an almost black powder by drying the yellow precipitate formed when hydrochloric acid is added to a solution of a thiostannate.
Dropsical liquids are usually pale yellow or greenish, limpid, with a saltish taste and alkaline reaction, and a specific gravity ranging from 1005 to 1024.
The action is very rapid, and the product, which rises to the top of the acids, is separated and washed successively with cold and then tepid water, and finally with water made slightly alkaline with sodium carbonate or hydroxide, to remove all adhering or dissolved acids which would otherwise render the product very unstable.
Some glycerin may be re-formed, but with very strong alkaline solutions little of the glycerin molecule escapes destruction, oxalic acid and several other products resulting.
The explanation is that in an alkaline medium at body heat nitroglycerin yields a nitrite, probably as a preliminary stage of resolution.
Nitroglycerin shaken up with warm very dilute alkaline solutions, as sodium carbonate, for a few minutes only, always yields sufficient nitrite to give the diazoreaction; and, as stated, strong alkaline solutions always produce some nitrite as one of the decomposition products.
Sometimes acid sometimes alkaline properties predominated in the juices and secretions of the body, and produced corresponding disturbances.
They combine readily with the alkyl iodides to form alkyl acridinium iodides, which are readily transformed by the action of alkaline potassium ferricyanide to N-alkyl acridones.
Magnesian limestone mixed and fused with sand and an alkaline carbonate produces a permanent glass.
It is found in the form of oxide (silica), either anhydrous or hydrated as quartz, flint, sand, chalcedony, tridymite, opal, &c., but occurs chiefly in the form of silicates of aluminium, magnesium, iron, and the alkali and alkaline earth metals, forming the chief constituent of various clays, soils and rocks.
On fusion with alkaline carbonates and hydroxides it undergoes oxidation to silica which dissolves on the excess of alkali yielding an alkaline silicate.
When heated with the alkali and alkaline earth metals it yields silicon and the corresponding metallic chlorides.
The acid carbonates of the alkali metals can be prepared by saturating an aqueous solution of the alkaline hydroxide with carbon dioxide, M OH+ C02= Mhco 3, and from these acid salts the normal salts may be obtained by gentle heating, carbon dioxide and water being produced at the same time, 2Mhco 3 = M2C03+H02+C02.
Most other carbonates are formed by precipitation of salts of the metals by means of alkaline carbonates.
The alkaline carbonates undergo only a very slight decomposition, even at a very bright red heat.
It is not very stable, water decomposing it into alcohol and the alkaline carbonate.
The metals of the alkalis and alkaline earths, also magnesium, burn in sulphur vapour as they do in oxygen.
It reduces ammoniacal silver solutions in the cold, and alkaline copper solutions on boiling.
In some factories for refining sugar made from beet or canes this system of carbonatation is used, and enables the refiner to work with syrups distinctly alkaline and to economize a notable amount of animal charcoal.