Barium oxide oxidizing agent

Harjum Oxide. This compound [1304-28-5] (Class 1, nonregenerative) is used primarily as a laboratory drying agent (4). It is the only drying agent that continues to dry even at red heat. Barium oxide is relatively expensive and cannot be regenerated by conventional methods. Therefore, it is not used extensively in commercial appHcations (see Barium COMPOUNDS). 

In a related reaction, primary aromatic amines have been oxidized to azo compounds by a variety of oxidizing agents, among them Mn02, lead tetraacetate, O2 and a base, barium permanganate, and sodium perborate in acetic acid, tert Butyl hydroperoxide has been used to oxidize certain primary amines to azoxy compounds. 

Anhydrous sodium sulphate, even when freshly ignited before use, is much less active than calcium chloride. It is used when a substitute for calcium chloride is indicated for the reasons given above. For solutions of basic substances ignited potassium carbonate, solid potassium hydroxide, and barium oxide are much used as drying agents. 

Barium bromate [Ba(BrO )2] is used as a corrosion inhibitor to prevent rust and as an oxidizing agent and chemical reagent. 

The aqueous solution of barium sulfide oxidizes slowly in the air forming elemental sulfur and various anions of sulfur including sulfite, thiosulfate, polysulfides and sulfate. The yellow color of barium sulfide solution is attributed to the presence of dissolved elemental sulfur that results from its slow oxidation in the air. In the presence of an oxidizing agent, barium sulfate is formed. Violent to explosive oxidation may occur when heated with strong oxidants such as phosphorus pentoxide or potassium chlorate. 

Treatment of barium peroxide, Ba02 with a concentrated solution of magnesium sulfate yields magnesium peroxide Mg02, a white powdery material used as a bleaching and oxidizing agent, and as an antacid in medicine. 

Fused alkalies, particularly potassium and barium hydroxides, are corrosive to platinum. In the presence of oxygen or oxidizing agents this corrosive action of fused alkalies increases. Also, cyanide and nitrates of alkali metals in fused state are corrosive to platinum. 

Chlorine is nearly always prepared in the laboratory by the action of an oxidizing agent—manganese dioxide, lead dioxide, barium dioxide, potassium dichromate,... 

Thiols, sulfoxides, sulfones, disulfides,407 and other sulfur compounds can be oxidized to sulfonic acids with many oxidizing agents, though for synthetic purposes the reaction is most important for thiols.408 Among oxidizing agents used are boiling nitric acid and barium... 

It can be seen that the (111) state is highly stable with respect to disproportionation in aqueous solution and is extremely difficult to oxidize or reduce. There is evidence for the existence of the (II) state since tracer amounts of amencium have been reduced by sodium amalgam and precipitated with barium chloride or europium sulfate as earner. The (IV) state is very unstable in solution the potential for americium(III)-ameridum(IV) was determined by thermal measurements involving solid Am02. Amencium can be oxidized to the (V) or (VI) state with strong oxidizing agents, and the potential for the americium(V)-americium(Vl) couple was determined potentiometrically. 

The intermediate stages of the reaction are indicated by the scheme NH(P0C12)2 —>N(P0C12)3, and this product, on hydrolysis, furnishes the acid in question. The free acid cannot be isolated, though lead, barium, and silver salts can be readily obtained. The alkali salts are crystalline and soluble in water. Oxidizing agents convert the soln. into orthophosphates. 

Alpha-amylase is most active at its pH optimum of 6.3 to 6.8.108,109 It is inactive at pH values below 4 and above 9. Enzymic starch conversion is terminated by raising the temperature until enzyme denaturation occurs or by the addition of enzyme poisons, such as the ions of copper, mercury or zinc. Inactivation can also be achieved by moving the pH outside the enzyme s active limits or by the addition of oxidizing agents, such as sodium hypochlorite, hydrogen peroxide or barium peroxide. 

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