Cations barium

Mandolini and Masci provided further information on this question quite recently by demonstrating that polyethylene glycol dibromides undergo partial hydrolysis and then cyclization in water containing Ba ions. According to the report, yields were higher in this reaction when barium cation was present than when it was absent. 

Fukishi and Hiiro [222] determined sulfide in seawater by this technique. The method is based on the generation of hydrogen sulfide by the addition of sulfuric acid to the water sample. The gas permeated through a microporous polytetrafluoroethylene (PTFE) tube, and was collected in a sodium hydroxide solution. The carbon dioxide in the permeate was removed by adding a barium cation-exchange resin to the sodium hydroxide solution. Injection into the... 

Chemists did not discover the mineral witherite (BaCO ) until the eighteenth century. Carl Wilhelm Scheele (1742—1786) discovered barium oxide in 1774, but he did not isolate or identify the element barium. It was not until 1808 that Sir Humphry Davy used molten barium compounds (baryta) as an electrolyte to separate, by electrolysis, the barium cations, which were deposited at the negative cathode as metallic barium. Therefore, Davy received the credit for bariums discovery. 

The inverse technique, which makes use of complexation of compounds to the product such that it becomes insoluble (e.g. fatty acids with barium cations), is also applied. These methods are also applicable for strains that do not grow on the screening compound due to lack of a complete metabolic pathway for the starting material. A variation on this theme is the trapping of radioactive tracers, such as... 

A< Ba(Q02)2.Bcirium is an alkaline ecirth metal (Group IIA) and thus has a chcii e of -1-2. You should recognize chlorite as the name of a polyatomic ion. In fact, any anion name that doesn t end in -ide should scream polyatomic ion to you. As Table 6-1 shows, chlorite is ClOj , which reveals that the chlorite ion has a-1 charge. Two chlorite ions cire necessary to neutralize the -1-2 chcirge of a single barium cation, so the chemical formula is Ba(C102)2-... 

A plethora of crown ether- or cryptand type molecules have been reported. Some of them are depicted below to show their diversity and versatility. Lariat azaether containing cyclen macrocycle 208 [36] and azaethers involving triazole 209 [37], furane or pyrrole containing macrocycles which can complex two copper 210 [38] or one barium cations 211 [39], spiro-linked crown ethers 212 [40] andcagecompounds 213 [41] which, in addition to two alkali cations, could... 

The barium cation (ionic radius 1.43 A) has a good compatibility with [2.2.2]cryptands (cavity diameter ca. 2.8 A). This cryptand will solubilize even BaS04 in aqueous solution,486 and this phenomenon has been investigated with a view to removal of BaS04 scale deposited by the use of sea water as an injection fluid in oil-producing formations. The scale deposition can lead to blockage of wells.487... 

Reinhoudt and co-workers (101-105) have reported a series of Schiff base macrocyclic polyether ligand complexes prepared via barium cation-templated Schiff base condensation of the appropriate polyether dialdehyde with a diamine, in the presence of a transition metal or uranyl acetate, followed by removal of the Ba2+ template cation on subsequent addition of guanidinium sulfate (Scheme 19). The copperdl) and nickeldl) complexes (62) and (63) exhibit reversible redox couples... 

X and Y zeolites exchanged with potassium and barium cations and associated with an adequate solvent are efficient for paraxylene separation by adsorption. The design of the adsorbent as well as of the process are both critical to reach economical production of paraxylene. The complete system, adsorbent plus process with the chosen configuration - stand alone or hybrid (adsorption + crystallization) - has to be optimized. 

According to Sawa et al., the rate of coke deposition is lowered when dealuminated mordenite is exchanged with barium cations. After 8 hours on stream the amount of coke deposited per mole of reacted methanol diminished as the degree of barium exchange increased. This was explained by the weakening of Bronsted acid sites by the barium cations. 

There is one barium cation for each disulphonate anion. 

Salts of [0s(N02)5] have long been reported in the literature" with sodium, potassium, ammonium, magnesium, calcium, strontium and barium cations, but the anion in these salts is now known to be trflns-[0s(N0)(0H)(N02)4] ." The potassium salt, made from [OsCl ] " and excess KNO2," is a useful starting material for other nitrosyl complexes since the NO groups are easily displaced. The X-ray crystal structure of the anion is discussed below (p. 548). The anion exhibits a complex hydrolytic behaviour, alledgedly in accordance with the trans effect of the nitrosyl Ugand." ... 

Salts of [0s(N02)s] have long been reported in the literature with sodium, potassium, ammonium, magnesium, calcium, strontium and barium cations, but the anion in these salts is now... 

Since both of the original solutions were strong electrolytes, you would expect a mixture of the two solutions to also be a strong electrolyte. However, since the light dims, the mixture must contain fewer ions than the original solution. Indeed, from the sulfuric acid reacts with the OH from the barium hydroxide to form water. The barium cations react with the sulfate anions to form insoluble barium sulfate. 

The four carboxylic groups of the tetraacid (3) can be easily neutalized by the proper base in ethanol/water and therefore salts of several cations could be prepared without difficulties. They show in water at 20 C a solubility (mmol/1) of 5.0 for lithium, 2.2 for ammonium, 2.0 for cesium and potassium, 0.5 for sodium and 0.2 for barium cations. 

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