noun
definition
The chemical element (symbol Ba) with an atomic number of 56. It is a soft, reactive, silvery alkaline earth metal.
definition
A single atom of this element.
definition
Barium sulfate suspension.
Examples of barium in a Sentence
The next group may contain the white calcium, barium and strontium carbonates.
Beryllium and magnesium are permanent in dry air; calcium, strontium and barium, however, oxidize rapidly on exposure.
The metals comprising this group are never found in the uncombined condition, but occur most often in the form of carbonates and sulphates; they form oxides of the type RO, and in the case of calcium, strontium and barium, of the type R02.
In 1808 Davy isolated sodium and potassium; he then turned his attention to the preparation of metallic calcium, barium, strontium and magnesium.
The barium and magnesium salts of this acid are formed when baryta and magnesia are fused with cobalt sesquioxide.
Barium chloride is present in some natural waters, and when this is the case the interaction of sulphates results in a deposition of barytes, as has occurred in the pipes and water-boxes of the Newcastle-on-Tyne coal mines.
Commercially, barytes is used in the preparation of barium compounds, as a body for certain kinds of paper and cloth, and as a white pigment ("permanent white").
Ammonium carbonate is added to the filtrate; this precipitates calcium, strontium and barium.
An immediate precipitate indicates barium; a precipitate on standing indicates strontium.
The solution free from barium is treated with ammonia and ammonium sulphate, which precipitates strontium, and the calcium in the solution may be identified by the white precipitate with ammonium oxalate.
Horbaczewski's method, which consists in boiling the substance with strong potash, saturating the cold solution` with chlorine, adding hydrochloric acid, and boiling till no more chlorine is liberated, and then testing for sulphuric acid with barium chloride.
Neumann, who, in 1831, deduced from observations on many carbonates (calcium, magnesium, ferrous, zinc, barium and lead) that stoichiometric quantities (equimolecular weights) of compounds possess the same heat capacity.
Most of the rubber now manufactured is not combined with sulphur when in the form of sheets, but is mechanically incorporated with about one-tenth of its weight of that substance by means of the mixing rollers - any required pigment or other matter, such as whiting or barium sulphate, being added.
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.
Venetian white, Hamburg white and Dutch white are mixtures of one part of white lead with one, two and three parts of barium sulphate respectively.
Ammonium sulphide blackens it, and it is soluble in solution of ammonium acetate, which distinguishes it from barium sulphate.
Four miles lower down the Irfon valley, at the junction of the Cammarch and Irfon, and with a station on the London & North Western railway, is the village of Llangammarch, noted for its barium springs.
A hydrated tin trioxide, Sn03, was obtained by Spring by adding barium dioxide to a solution of stannous chloride and hydrochloric acid; the solution is dialysed, and the colloidal solution is evaporated to form a white mass of 2Sn03 H20.
The newer glasses, on the other hand, contain a much wider variety of chemical constituents, the most important being the oxides of barium, magnesium, aluminium and zinc, used either with or without the addition of the bases already named in reference to the older glasses, and - among acid bodies - boric anhydride (B20 3) which replaces the silica of the older glasses to a varying extent.
The materials employed are sand, sulphate of soda, nitrate of soda, calcspar and in some works carbonate of barium.
Silicofluoric acid, H2SiF6, is obtained as shown above, and also by the action of sulphuric acid on barium silicofluoride, or by absorbing silicon fluoride in aqueous hydrofluoric acid.
Many are found as minerals, the more important of such naturally occurring carbonates being cerussite (lead carbonate, PbC03), malachite and azurite (both basic copper carbonates), calamine (zinc carbonate, ZnCO 3), witherite (barium carbonate, BaCO 3), strontianite (strontium carbonate, SrC03), calcite (calcium carbonate, CaC03), dolomite (calcium magnesium carbonate, CaCO 3 MgCO 3), and sodium carbonate, Na 2 CO 3.
Dumas obtained barium methyl carbonate by the action of carbon dioxide on baryta dissolved in methyl alcohol (Ann., 1840, 35, p. 283).
Water, at ordinary or slightly elevated temperatures, is decomposed more or less readily, with evolution of hydrogen gas and formation of a basic hydrate, by (I) potassium (formation of KHO), sodium (NaHO), lithium (LiOH), barium, strontium, calcium (BaH 2 O 2, &c.); (2) magnesium, zinc, manganese (MgO 2 H 2, &c.).
Somewhat less volatile than the last-named group are the chlorides (MC1 2) of barium, strontium and calcium.
Barium and strontium have also been produced by electrometallurgical methods, but the processes have only a laboratory interest at present.
Aqueous alcohol becomes turbid when mixed with benzene, carbon disulphide or paraffin oil; when added to a solution of barium oxide in absolute alcohol, a white precipitate of barium hydroxide is formed.
At the same time any lead, calcium, barium and strontium present are precipitated as sulphates; it is therefore advantageous to remove these metals by the preliminary addition of sulphuric acid, which also serves to keep any basic iron salts in solution.
Rohrbach's solution, an aqueous solution of barium and mercuric iodides, introduced by Carl Rohrbach, has a density of 3.588.
The free acid may be obtained by decomposing the barium salt with sulphuric acid and concentrating the solution, when a crystalline mass of composition H 2 Te04.2H 2 O separates.
In a smaller degree these alkaline properties are shared by the less soluble hydrates of the "metals of the alkaline earths," calcium, barium and strontium, and by thallium hydrate.
The residue so obtained is then powdered and ignited with barium nitrate, which converts the iridium into its oxide and the osmium into barium osmiate.
The barium salt is extracted by water and boiled with nitric acid, when the osmium volatilizes in the form of its tetroxide.
As an alternative the osmiridium is fused with zinc, the regulus treated with hydrochloric acid, and then heated with barium nitrate and barium peroxide.
After fusion, the mass is finely powdered and treated with cold dilute hydrochloric acid; and when action has finished, nitric and sulphuric acids are added, the precipitated barium sulphate removed, the liquid distilled and the osmium precipitated as sulphide.
Ammonium chlorate, NH 4 C10 3, is obtained by neutralizing chloric acid with either ammonia or ammonium carbonate, or by precipitating barium, strontium or calcium chlorates with ammonium carbonate.
Ammonium nitrite, NH 4 NO 2, is formed by oxidizing ammonia with ozone or hydrogen peroxide; by precipitating barium or lead nitrites with ammonium sulphate, or silver nitrite with ammonium chloride.
The iodides can be prepared either by direct union of iodine with a metal, from hydriodic acid and a metal, oxide, hydroxide or carbonate, or by action of iodine on some metallic hydroxides or carbonates (such as those of potassium, sodium, barium, &c.; other products, however, are formed at the same time).
Iodic Acid, H10 3, can be prepared by dissolving iodine pentoxide in water; by boiling iodine with fuming nitric acid, 61+10HN03= 6H10 3 +10N0+2H 2 O; by decomposing barium iodate with the calculated quantity of sulphuric acid, previously diluted with water, or by suspending iodine in water and passing in chlorine, 12+5C12+ 6H 2 0=2H10 3 +10HC1.
The free acid forms dark red deliquescent crystals and is obtained by decomposing the silver salt with hydrochloric acid, or the barium salt with dilute sulphuric acid.
Normal chromates on the addition of silver nitrate give a red precipitate of silver chromate, easily soluble in ammonia, and with barium chloride a yellow precipitate of barium chromate, insoluble in acetic acid.
In the spectrum of barium no series has yet been recognized.
It may be purified by redistillation over barium and silver nitrates, followed by treatment of the distillate with a stream of ozonized air.
To purify the oxide, it is dissolved in dilute hydrochloric acid until the acid is neatly neutralized, the solution is cooled, filtered, and baryta water is added until a faint permanent white precipitate of hydrated barium peroxide appears; the solution is now filtered, and a concentrated solution of baryta water is added to the filtrate, when a crystalline precipitate of hydrated barium peroxide, Ba0 2 8 H 2 0, is thrown down.
The solution is filtered, and the barium precipitated by sulphuric acid.
The ester is separated from the solution by means of its barium salt, and the salt decomposed by the addition of the calculated amount of sulphuric acid.
After removing the uranium, it was found that the bismuth separated with a very active substance - polonium; this element was afterwards isolated by Marckwald, and proved to be identical with his radiotellurium; that the barium could be separated with another active substance - radium; whilst a third fraction, composed mainly of the rare earths (thorium, &c.), yielded to Debierne another radioactive element - actinium, which proved to be identical with the emanium of Giesel.
There is a mass of evidence to show that radium is to be regarded as an element, and in general its properties resemble those of the metals of the alkaline earths, more particularly barium.
To the bunsen flame a radium salt imparts an intense carmine-red colour (barium gives a green).
The nitrate Be(NO,)2.3H20 is prepared by adding barium nitrate to ber y llium sulphate solution; it crystallizes with difficulty and is very deliquescent.