Barium and Strontium Nitrates

Nitric acid is one of the most important industrial chemicals in the world. Its largest use is in the fertdizer industry for producing various nitrate fertd-izers. Such fertilizers include ammonium-, sodium-, potassium-, and calcium nitrates. Other major apphcations of nitric acid are in making nitrates and nitrooganics for use in explosives, gunpowder, and fireworks. Ammonium nitrate, nitroglycerine, nitrocellulose, and trinitrotoluenes are examples of such explosives, while barium and strontium nitrates are used in fireworks. 

Composition Mixtures of potassium perchlorate or barium and strontium nitrate with magnesium powder or flakes, P4. 

Barium nitrate would be the best of the three from the standpoint of physical stability and also of heat concentration because barium oxide has considerably better refractory properties than either potassium or sodium oxide. However, the high equivalent weight of barium limits its usefulness. Barium and strontium nitrates are indispensable for green and red effects and can also be used combined for white light. In combination with potassium perchlorate and aluminum, barium nitrate is part of standard photoflash powder. Ammonium and guanidine nitrate are sometimes used because of their gas-forming properties, and lead and silver nitrate can be found in special applications. 

In general, the chemistry of inorganic lead compounds is similar to that of the alkaline-earth elements. Thus the carbonate, nitrate, and sulfate of lead are isomorphous with the corresponding compounds of calcium, barium, and strontium. In addition, many inorganic lead compounds possess two or more crystalline forms having different properties. For example, the oxides and the sulfide of bivalent lead are frequendy colored as a result of their state of crystallisation. Pure, tetragonal a-PbO is red pure, orthorhombic P PbO is yeUow and crystals of lead sulfide, PbS, have a black, metallic luster. 

Strontium has a valence of +2 and forms compounds that resemble the compounds of the other alkaline-earth metals (see Barium compounds Calcium compounds). Although many strontium compounds are known, there are only a few that have commercial importance and, of these, strontium carbonate [1633-05-2] SrCO, and strontium nitrate [10042-76-9], Sr(N03)2, are made in the largest quantities. The mineral celestite [7759-02-6], SrSO, is the raw material from which the carbonate or the nitrate is made. 

Sulphuric Acid. — On diluting 5 gm. of hydrosilicofluoric acid with 10 cc. of water and adding a solution of barium-free strontium nitrate, no precipitate should form, even on standing twelve hours. 

Nitric acid is usually monobasic, forming a series of salts, the nitrates. The basic salts have been discussed by A. Ditte,11 E. Groschuff, and others—see, for example, the basic lead nitrates. The nitrates are usually made by the action of the acid on the metal, hydroxide, oxide, carbonate, etc. According to H. Braconnot, the cone, acid does not decompose dehydrated sodium, barium, calcium, or lead carbonate, even when boiling, because the nitrates of these bases are insoluble in the cone, acid, and a surface film of nitrate protects the remainder of the carbonate from the acid. Potassium carbonate is decomposed by the cone, acid because the nitrate is soluble in the cone. acid. J. Pelouze said that an alcoholic soln. of nitric acid does not act on potassium carbonate, but it acts slowly on sodium, barium, and magnesium carbonates, and rapidly on calcium and strontium carbonates because, added H. Braconnot, calcium and strontium nitrates are readily dissolved by alcohol, whereas potassium nitrate is but sparingly soluble in that menstruum. Potassium hydroxide resists attack by a soln. of nitric acid in ether unless the mixture is boiled or shaken. A. A. Kazantzeff discussed the influence of nitric acid on the solubilities of the nitrates. 

A. Ihre prepared barium mesoperiodate, Ba3(I05)2, and also strontium meso-periodate, Sr3(I05)2, by adding ammonia to a dil. aq. soln. of sodium metaperiodate, and dropping the mixture into a soln. of barium or strontium nitrate as the case might be 3Sr(N03)2+2Na4l209=Sr3(I05)2+2NaI04+6NaN03. 

Pulverized barium or strontium nitrate consolidates into a hard mass over a period of time. These substances are dried above 100°C and stored in a moistureproof container,e.g. a steel drum. Nitrates are sometimes placed in a iron pan and heated over a direct heat with constant stirring. It is not dangerous unless a combustible material is added... 

Barium nitrate and Strontium nitrate when in oombi-nation with potassium chlorate and sh ac or other gums form a sensitive mixtxue and this condition is largdy increased when powdered charcoal is added. Care is therefore urged to avoid all unneccessary fri on when handling same. 

Application of solid-liquid extraction in the field of Inorganic Chemistry can be illustrated by taking the examples of separation of (i) lithium chloride from the chlorides of other members of the alkali metal group and (ii) calcium nitrate from the nitrates of other members of the alkaline earth group. The solubilities of sodium chloride and potassium chloride are very small in -hexanol and 2-ethylhexanol, whereas the solubility of lithium chloride is large enough so that it can be separated from a mixture of the three chlorides by extraction with these solvents. Similarly, using a 50-50 per cent mixture of absolute ethanol and ether calcium nitrate can be removed from a mixture of the anhydrous nitrates of calcium, barium and strontium. 

Under favorable circumstances, an initial precipitation reaction can be selected that will separate the radionuclide of interest from most contaminants. An example from the group separations in Table 3.2 is the precipitation of strontium nitrate in concentrated nitric acid. The element of interest may be accompanied by several other elements, usually in the same periodic group, as indicated in the table. Barium and radium nitrate, for example, are also insoluble. If such specific precipitation reactions can be applied directly, the only additional processes will be separation from these similar elements and preparation of the counting source. 

In older formulations, barium nitrate appears as the oxidant but with sodium oxalate added. Light output and other pertinent data for experimental flares containing both sodium and strontium nitrate in varying proportions are found in an NAD Crane report. ... 

We must now return to the less esoteric aspects of colored flame production. A practical approach is the use of the nitrates of barium and strontium as oxidizers followed by their partial conversion into halides by combining them with the oxidizers potassium chlorate or perchlorate. Eliminating the chlorate for military purposes because of... 

Alkali bromides, chlorides, sulfates, and nitrates interfere only when very small amounts of iodide are to be detected. Bromides have the greatest deleterious effect however, when the amount of bromide is approximately known, small amounts of iodine may still be detected if a comparative test is carried out. Metal salts which give colored aqueous solutions interfere (Fe , UOa, Ni, Cu, Co). Cyanides, mercuric, silver, and manganese salts impair the reaction, as do compounds which reduce Ce. In such cases the difficulty may occasionally be averted by using more concentrated ceric solutions. Under the experimental conditions, barium and strontium salts are precipitated as sulfates, which are colored yellow by coprecipitation of ceric salt. Osmium salts behave similarly to iodides. 

Ca + may also be detected via precipitation with oxalic acid as calcium oxalate, which is very poorly soluble. In a first reaction, barium and strontium must be eliminated as sulfates and other disturbing ions must be complexed by complexone(III). The latter, if added in excess, must not prevent the calcium precipitation. Its excess is eliminated by adding aluminum nitrate. 

The metaplumbates of strontium and bariiun M"Pb03 are made by fusion of strontium or barium nitrates with lead(II) oxides. The oxides of nitrogen released convert the lead(II) to lead(IV). Calcium orthoplumbate Ca2Pb04 is formed when calcium nitrate and lead(II) oxide are fused in the stoichiometry Ca(N03)2.Pb0. The barium and strontium orthoplumbates are prepared by heating barium or strontium carbonates with lead(II) oxide in the stoichiometry [MC03]2.PbO the necessary oxidation is caused by the atmo-sphere o. 

Barium is a member of the aLkaline-earth group of elements in Group 2 (IIA) of the period table. Calcium [7440-70-2], Ca, strontium [7440-24-6], Sr, and barium form a closely aUied series in which the chemical and physical properties of the elements and thek compounds vary systematically with increa sing size, the ionic and electropositive nature being greatest for barium (see Calcium AND CALCIUM ALLOYS Calcium compounds Strontium and STRONTIUM compounds). As size increases, hydration tendencies of the crystalline salts increase solubiUties of sulfates, nitrates, chlorides, etc, decrease (except duorides) solubiUties of haUdes in ethanol decrease thermal stabiUties of carbonates, nitrates, and peroxides increase and the rates of reaction of the metals with hydrogen increase. 

Nickel, Copper and Beryllium nitrates Calcium, Magnesium, Strontium and Barium chlorides (5,7]... 

Pesticides may change the soil s element content. Some pesticides may increase plants micro- and macroelement content, such as nitrogen, phosphorus, calcium, potassium, magnesium, manganese, iron, copper, barium, aluminum, strontium and zinc, whereas others decrease these or other elements. Pesticides may cause ammoniac compounds to accumulate in the soil. Dimethoate and fluometuron increase nitrates in the soil, while DDT, carbaryl and HCH sharply decrease them. When prometrin was used, soil nitrate content decreased by 30-40% [3]. 

Barium sulfide explodes weakly on heating with lead dioxide or potassium chlorate, and strongly with potassium nitrate. Calcium and strontium sulfides are similar. 

Palladium catalysts resemble closely the platinum catalysts. Palladium oxide (PdO) is prepared from palladium chloride and sodium nitrate by fusion at 575-600° [29,30]. Elemental palladium is obtained by reduction of palladium chloride with sodium borohydride [27, 31], Supported palladium catalysts are prepared with the contents of 5% or 10% of palladium on charcoal, calcium carbonate and barium sulfate [32], Sometimes a special support can increase the selectivity of palladium. Palladium on strontium carbonate (2%) was successfully used for reduction of just y, (5-double bond in a system of oc, / , y, (5-unsaturated ketone [ii]. 

This reaction corresponds to 30.6% available oxygen. At lower reaction temperatures, barium nitrate produces nitrogen oxides CNO and NO 2) instead of nitrogen gas, as does strontium nitrate... 

To use potassium nitrate in colored flame mixtures, it is necessary to include magnesium as a fuel to raise the flame temperature. A source of chlorine is also needed for formation of volatile BaCl (green), or SrCl (red) emitters. The presence of chlorine in the flame also aids by hindering the formation of magnesium oxide and strontium or barium oxide, all of which will hurt the color quality. Shidlovskiy suggests a minimum of 15% chlorine donor in a color composition when magnesinm metal is nsed as a fuel [5]. 

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