Peroxide, barium strontium

The corresponding sodium, derivative is readily prepared by fusing together ruthenium and sodium peroxide.3 The silver, barium, strontium, calcium, and magnesium salts are also known. 

In spite of widespread usage of these compounds, the stmctures of only the calcium, barium, and strontium compounds are reasonably weU-estabhshed. The materials are generally made by trituratiag the oxides, or hydroxides, with aqueous hydrogen peroxide and dryiag the soHd products. The commercial products are typically mixtures of the peroxides with varyiag amounts of hydroxides, oxides, carbonates, hydrates, and peroxohydrates. 

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. 

Compared to the hydroxides of calcium and strontiuim, barium hydroxide is the most water-soluble and also the strongest base. Additionally, barium hydroxide is more difficult to convert to the oxide by heating than are the corresponding hydroxides of calcium and strontium. Barium oxide is more readily converted to the peroxide than are the oxides of the other alkaline earths. 

A.B. Tsent-Kurnakova R.P. Vasd eva, Synthesis of Calcium, Strontium, and Barium Peroxide Compounds in Hydrogen Peroxide Vapours , IzvAkadNaukSSSR,SerKhim (12), 2738-40 (1967) CA 68, 110875 (1968)... 

Determination of Barium and Strontium Peroxides (Active Oxygen) in Igniters In Small Arms Tracer Ammunition , FATR T-76059 (1975) 33) ChemRubHndbk (1975), B-71... 

Lead peroxide is even more active than the oxide. It reacts violently with sulphur and sulphides. When it is ground up with sulphur, the mixture combusts. With hydrogen sulphide, the reaction is very exothermic and causes peroxide to incandesce and hydrogen sulphide to combust. Finally, it reacts violently with calcium, strontium and barium sulphides on heating. 

Impact sensitivities of mixtures of red phosphorus with various oxidants were determined in a direct drop-ball method, which indicated higher sensitivities than those determined with an indirect striker mechanism. Mixtures with silver chlorate were most sensitive, those with bromates, chlorates and chlorites were extremely sensitive, and mixtures with sodium peroxide and potassium superoxide were more sensitive than those with barium, calcium, magnesium, strontium or zinc peroxides. Mixtures with perchlorates or iodates had sensitivities comparable to those of unmixed explosives, such as lead azide, 3,5-dinitrobenzenediazonium-2-oxide etc. 

Ammonium nitrate Ammonium perchlorate Barium chlorate (hydrate) Barium chromate Barium nitrate Barium peroxide Iron oxide Iron oxide Lead chromate Lead oxide (red lead) Lead peroxide Potassium chlorate Potassium nitrate Potassium perchlorate Sodium nitrate Strontium nitrate... 

How can the oxides, peroxides, and hydroxides of the alkaline-earth metals be prepared What are the commercial names of calcium and barium hydroxide solutions How do the solubility, basic properties, and thermal stability of the hydroxides change in the series calcium-strontium-barium ... 

Five grains of anhydrous strontium nitrate (or the equivalent weight of the 4-hydrate) are dissolved in 50 ml of 3% hydrogen peroxide and mixed with a solution of 7 ml of concentrated aqueous ammonia in 100ml of water. The peroxide 8-hydrate is converted to the anhydrous compound by heating it at 300 C for about 4 hours in dry CCh-free oxygen, as described under the procedure for barium. 

A similar but less complete trend appears in the reactions of the alkaline earth metals with oxygen. Treatment with excess 02 yields monoxides in the cases of beryllium, magnesium, and calcium barium, however, forms the peroxide, Ba02, whereas strontium gives a mixture of monoxide and peroxide. 

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