Alkali-metals Sentence Examples
The metallic derivatives (phenolates, phenates or carbolates) of the alkali metals are obtained by dissolving phenol in a solution of a caustic alkali, in the absence of air.
Most metals form carbonates (aluminium and chromium are exceptions), the alkali metals yielding both acid and normal carbonates of the types Mhco 3 and M 2 CO 3 (M = one atom of a monovalent metal); whilst bismuth, copper and magnesium appear only to form basic carbonates.
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.
All carbonates, except those of the alkali metals and of thallium, are insoluble in water; and the majority decompose when heated strongly, carbon dioxide being liberated and a residue of an oxide of the metal left.
Only the salts of the alkali metals are soluble in water.Advertisement
Various compounds of the alkali metals with bismuth, antimony, tin and lead have been prepared in a pure state.
It combines with the chlorides of the alkali metals to form characteristic double salts of the type OsC1 4.2MC1 (osmichlorides).
It does not burn, and does not support ordinary combustion, but the alkali metals and magnesium, if strongly heated, will continue to burn in the gas with formation of oxides and liberation of carbon.
The iodates of the alkali metals are, however, readily soluble in water (except potassium iodate).
In the spectra of the alkali metals each line of the trunk is a doublet, and we may speak of a twin trunk springing out of the same root.Advertisement
This form has the advantage that the constants of the equation when applied to the spectra of the alkali metals show marked regularities.
All its lines arrange themselves in two families of series, in other words, the spectrum looks like that of the superposition of two spectra similar to those presented by the alkali metals.
Pringsheim, who, by a series of experiments of undoubted merit, tried to establish that the emission of the line spectra of the alkali metals was invariably associated with a reduction of the metallic oxide.
Previous to Stark's investigation P. Lenard 2 had concluded that the carriers of certain of the lines of the flame spectra of the alkali metals are positively charged.
This compound possesses a heat of formation so much lower that electrically it needs but a voltage of 0.9 to decomplose it, and it is easily soluble in the fused sulphides of the alkali metals.Advertisement
Double sulphates of beryllium and the alkali metals are known, e.g.
It forms double salts with the chlorides of the alkali metals.
It combines with the sulphates of the alkali metals to form double salts.
Chlorine is never found in nature in the uncombined condition, but in combination with the alkali metals it occurs widely distributed in the form of rock-salt (sodium chloride); as sylvine and carnallite, at Stassfiirt; and to a smaller extent in various other minerals such as matlockite and horn-mercury.
Some metallic chlorides readily form double chlorides, the most important of these double salts being the platinochlorides of the alkali metals.Advertisement
Sulphur, phosphorus, carbon compounds, and the alkali metals react violently with the gas, taking fire with explosive decomposition.
It combines with chlorides of the alkali metals to form double salts, and also with barium, calcium, strontium, and magnesium chlorides.
Bases of the alkali metals give with it four series of salts; these are stable except in alkaline solutions, in which they absorb oxygen and turn brown.
These compounds are brought into solution by means of polysulphides of the alkali metals and the resultant liquor run into the cathode compartment of a bath, which is divided by diaphragms into a series of anode and cathode chambers; the anode divisions being closed and gas-tight, and containing carbon or platinum electrodes.
The arsenites of the alkali metals are soluble in water, those of the other metals are insoluble in water, but are readily soluble in acids.Advertisement
The thioarsenites and thioarsenates of the alkali metals are easily soluble in water, and are readily decomposed by the action of mineral acids.
The bichromates are usually of a red or reddishbrown colour, those of the alkali metals being readily soluble in water.
They become more reactive Why are the alkali metals together in group 1?
The tellurides of the alkali metals immediately decompose on exposure to air, with liberation of tellurium.