Barium hydroxide, preparation

Phosphine can be prepared by the reaction of a strong alkali with white phosphorus potassium, sodium and barium hydroxides may be used ... 

Prepare a solution of 41 g. of anhydrous palladium chloride (1) in 10 ml. of concentrated hydrochloric acid and 25 ml. of water (as in A). Add all at once 60 ml. of 6iV-sulphuric acid to a rapidly stirred, hot (80°) solution of 63 1 g. of A.R. crystallised barium hydroxide in 600 ml. of water contained in a 2-htre beaker. Add more 6iV-sulphuric acid to render the suspension just acid to htmus (5). Introduce the palladium chloride solution and 4 ml. of 37 per cent, formaldehyde solution into the hot mechanically stirred suspension of barium sulphate. Render the suspension slightly alkaline with 30 per cent, sodium hydroxide solution, continue the stirring for 5 minutes longer, and allow the catalyst to settle. Decant the clear supernatant hquid, replace it by water and resuspend the catalyst. Wash the catalyst by decantation 8-10 times and then collect it on a medium - porosity sintered glass funnel, wash it with five 25 ml. portions of water and suck as dry as possible. Dry the funnel and contents at 80°, powder the catalyst (48 g.), and store it in a tightly stoppered bottle. 

Barium nitrite [13465-94-6] Ba(N02)2, crystallines from aqueous solution as barium nitrite monohydrate [7787-38-4], Ba(N02)2 H2O, which has yellowish hexagonal crystals, sp gr 3.173, solubihty 54.8 g Ba(NO2)2/100 g H2O at 0°C, 319 g at 100°C. The monohydrate loses its water of crystallization at 116°C. Anhydrous barium nitrite, sp gr 3.234, melts at 267°C and decomposes at 270 °C into BaO, NO, and N2. Barium nitrite may be prepared by crystallization from a solution of equivalent quantities of barium chloride and sodium nitrite, by thermal decomposition of barium nitrate in an atmosphere of NO, or by treating barium hydroxide or barium carbonate with the gaseous oxidiation products of ammonia. It has been used in diazotization reactions. 

Calcium hydroxide is a better catalyst at 40-90° than barium hydroxide, magnesium hydroxide, sodium hydroxide, and sodium carbonate for preparing pentaerythritol. Corbellini and... 

Cellobiose was prepared first by Skraup and Konig by the saponification of the octaacetate with alcoholic potassium hydroxide, and the method was improved by Pringsheim and Merkatz.3 Aqueous barium hydroxide also has been employed for the purpose, and methyl alcoholic ammonia has been used extensively for the hydrolysis of carbohydrate acetates. The method of catalytic hydrolysis with a small quantity of sodium methylate was introduced by Zemplen,i who considered the action to be due to the addition of the reagent to the ester-carbonyl groups of the sugar acetate and the decomposition of the addition compound by reaction with alcohol. The present procedure, reported by Zemplen, Gerecs, and Hadacsy, is a considerable improvement over the original method (see Note 2). 

Barium carbonate can be prepared by carbonation of either barium hydroxide (Yagi etai, 1988) or barium sulphate (Kubota etai, 1990) ... 

The ease with which thiophenes are formed in the reaction of acetylenic epoxides " and of polyacetylenes with hydrogen sulfide is of great interest in connection with the biosynthesis of the naturally occurring thiophenes (cf. Section VIH,A) and also of preparative importance. 2-Methyl-l,2-oxido-5-hexene-3-yne (56) in water containing barium hydroxide reacts with HzS at 50°C to give 4-... 

Consider barium hydroxide, Ba(OH)2, a white, powdery substance. Student A prepares a solution of Ba(OH)z by dissolving 4.23 g of Ba(OH)2 in enough water to make 455 mL of solution. 

Hydrochloric acid and sulphuric acid are widely employed in the preparation of standard solutions of acids. Both of these are commercially available as concentrated solutions concentrated hydrochloric acid is about 10.5- 12M, and concentrated sulphuric acid is about 18M. By suitable dilution, solutions of any desired approximate concentration may be readily prepared. Hydrochloric acid is generally preferred, since most chlorides are soluble in water. Sulphuric acid forms insoluble salts with calcium and barium hydroxides for titration of hot liquids or for determinations which require boiling for some time with excess of acid, standard sulphuric acid is, however, preferable. Nitric acid is rarely employed, because it almost invariably contains a little nitrous acid, which has a destructive action upon many indicators. 

Methyliminodiacetic acid has been prepared by the action of methylamine on formaldehyde cyanohydrin, subsequent hydrolysis of the dinitrile with barium hydroxide, and regeneration from the barium salt with sulfuric acid.1 This method was found by the submitter to be much less satisfactory than the procedure given above. 

Mitkevich, Preparation of Barium Peroxide From Hydrogen Peroxide and Barium Hydroxide , KhimPromUkr (6), 17-19 (1968) CA... 

Calculate the concentrations of each of the following solutions (a) the molality of chloride ions in an aqueous solution of iron(lll) chloride for which is 0.0205 (b) the molality of hydroxide ions in a solution prepared from 9.25 g of barium hydroxide dissolved in 183 g of water. (c) the molality of 12.00 M NH,(aq) with a density of... 

Interaction is exothermic, and if air is present, incandescence may occur with freshly prepared granular material. Admixture with oxygen causes a violent explosion [1], Soda-lime, used to absorb hydrogen sulfide, will subsequently react with atmospheric oxygen and especially carbon dioxide (from the solid coolant) with a sufficient exotherm in contact with moist paper wipes (in a laboratory waste bin) to cause ignition [2], Spent material should be saturated with water before separate disposal. Mixture analogous to soda-lime, such as barium hydroxide with potassium or sodium hydroxides, also behave similarly [1],... 

They prepared the acetate by means of acetic anhydride in dry pyridine and purified it by separation from an acetic acid solution to which warm methyl alcohol had been added n ]n2 = — 22.70° (c = 10, acetic acid), m. p. 206-208°. In the presence of barium hydroxide irisin formed an insoluble product whose composition was represented by 6(C6Hi0O6)-Ba(OH)2. In contrast to inulin, these authors found that Takadiastase at pH 5 to 5.5 did not hydrolyze irisin. 

Phenylacetylene has been prepared by the elimination of carbon dioxide from pbenylpropiolic acid by means of phenol1 or aniline 2 or by heating with barium hydroxide 3 from styrene dibromide, by heating with potassium hydroxide in alcohol 4 by heating /3-bromo or chloro styrene with sodium ethylate or potassium hydroxide in alcohol 5 by passing the vapors of a-dichloroethylbenzene over hot soda lime 6 by the action of alcoholic potassium hydroxide on dibenzal-acetone tetra-... 

Methylenedinitramine (l,3-dinitro-l,3-diazapropane) (168) can be prepared from the nitration of the bis-acetamide (166), followed by hydrolysis of the product (167) with barium hydroxide and subsequent acidification.Methylenedinitramine has no practical value as an explosive due to its facile decomposition in solution. 

Barium cyanide is prepared by reacting barium hydroxide with hydrocyanic acid ... 

Barium hydroxide is used to produce barium soaps which are additives for high temperature lubricants. Other chemical applications include refining of vegetable oils vulcanization of synthetic rubber in drilling fluids in corrosion inhibitors as an ingredient in sealing compositions in plastics stabilizers for softening water and to prepare other alkalies. 

Barium hydroxide is made by dissolving barium oxide in hot water. The octahydrate, Ba(0H)2 8H20, crystaUizes upon cooling. It also is prepared by precipitation with caustic soda from an aqueous solution of barium sulfide ... 

The compound also may be prepared by other methods. These include ignition of barium and titanium alcoholates in an organic solvent treatment of tetraethyl titanate or other alkyl ester of titanium with an aqueous solution of barium hydroxide and ignition of barium titanyloxalate. 

Rubidium hydroxide may be obtained as an intermediate in recovering rubidium metal from mineral lepidohte (see Rubidium). In the laboratory it may be prepared by adding barium hydroxide to a solution of rubidium sulfate. The insoluble barium sulfate is separated by filtration ... 

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