Oxides Moderately soluble

Boron trioxide is not particularly soluble in water but it slowly dissolves to form both dioxo(HB02)(meta) and trioxo(H3B03) (ortho) boric acids. It is a dimorphous oxide and exists as either a glassy or a crystalline solid. Boron trioxide is an acidic oxide and combines with metal oxides and hydroxides to form borates, some of which have characteristic colours—a fact utilised in analysis as the "borax bead test , cf alumina p. 150. Boric acid. H3BO3. properly called trioxoboric acid, may be prepared by adding excess hydrochloric or sulphuric acid to a hot saturated solution of borax, sodium heptaoxotetraborate, Na2B407, when the only moderately soluble boric acid separates as white flaky crystals on cooling. Boric acid is a very weak monobasic acid it is, in fact, a Lewis acid since its acidity is due to an initial acceptance of a lone pair of electrons from water rather than direct proton donation as in the case of Lowry-Bronsted acids, i.e. 

Some nonmalignant respiratory effects have been observed in experimental animals during acute or subchronic exposures. Soluble and moderately soluble compounds were more toxic than were insoluble compounds and produced different effects. Sulfate and subsulftde produced fibrosis whereas nickel oxide did not. 

Dipyridiue-chromium(VI) oxide2 was introduced as an oxidant for the conversion of acid-sensitive alcohols to carbonyl compounds by Poos, Arth, Beyler, and Sarett.3 The complex, dispersed in pyridine, smoothly converts secondary alcohols to ketones, but oxidations of primary alcohols to aldehydes are capricious.4 In 1968, Collins, Hess, and Frank found that anhydrous dipyridine-chromium(VI) oxide is moderately soluble in chlorinated hydrocarbons and chose dichloro-methane as the solvent.5 By this modification, primary and secondary alcohols were oxidized to aldehydes and ketones in yields of 87-98%. Subsequently Dauben, Lorber, and Fullerton showed that dichloro-methane solutions of the complex are also useful for accomplishing allylic oxidations.6... 

Hydrogen sulfide dissolves in water to give a solution of hydrosulfuric acid that, as a result of its oxidation by dissolved air, slowly becomes cloudy as S8 molecules form and then coagulate. Hydrosulfuric acid is a weak diprotic acid and the parent acid of the hydrogen sulfides (which contain the HS ion) and the sulfides (which contain the S2 ion). The sulfides of the s-block elements are moderately soluble, whereas the sulfides of the heavy p- and d-block metals are generally very insoluble. 

Those minerals whose solubilities are greater than those of most oxides and silicates, but lower than those of soluble salt minerals, are grouped as semisoluble salt minerals (also called salt-type minerals). The list comprising this particular minerals group is calcite, dolomite, magnesite, barite, gypsum, scheelite, carbonate, phosphate, sulfate and some others. These minerals are characterized mainly by their tonic bonding and as has already been pointed out, by their moderate solubility. 

Pale green hexagonal crystals (in partially oxidized form) or white amorphous powder (when pure) density 3.4g/cm3 decomposes on heating insoluble in water (1.5 mg/L at 20°C), Ksp 8.0 x IQ i soluble in acids moderately soluble in ammonium salt solutions insoluble in alkalies. 

Dark purple rhombohedral crystal density 2.703 g/cm stable in air decomposes at about 240°C moderately soluble in cold water, 6.38 g/lOOmL at 20°C, soluble in hot water, 25 g/lOOmL at 65°C decomposed by alcohol, acetone and many organic solvents causing their oxidation also decomposed by concentrated acids. 

The concentration of an inhaled anesthetic in the inspired gas mixture has direct effects on both the maximum tension that can be achieved in the alveoli and the rate of increase in its tension in arterial blood. Increases in the inspired anesthetic concentration increase the rate of induction of anesthesia by increasing the rate of transfer into the blood according to Fick s law (see Chapter 1). Advantage is taken of this effect in anesthetic practice with inhaled anesthetics that possess moderate blood solubility (eg, enflurane, isoflurane, and halothane). For example, a 1.5% concentration of isoflurane may be administered initially to increase the rate of rise in the brain concentration the inspired concentration is subsequently reduced to 0.75-1% when an adequate depth of anesthesia is achieved. In addition, these moderately soluble anesthetics are often administered in combination with a less soluble agent (eg, nitrous oxide) to reduce the time required for loss of consciousness and achievement of a surgical depth of anesthesia. 

Perchlorate Ammonium perchlorate [CAS 7790-98-9] (NH(4)CLO(4)) is a white crystalline substance. It is a powerful oxidizing material. A1J is the oxidizer used in the solidroekel boosters on the space shuttle. It is stable in pure form at ordinary temperature, but decomposes at a temperature of 150 degrees C or above. It becomes an explosive when mixed with finely divided organic materials. AP exhibits the same explosive sensitivity to shock as picric acid (Class A explosive). Sensitivity to shock and friction may be great when contaminated with small amounts of some impurities such as sulfur, powdered metals and carbonaceous materials. AP may explode when involved in fire. Periodate Ammonium penodate NH4IO4. white solid, moderately soluble. 

The melting point generally ascribed to the alpha form is 169.6°C, with decomposition occurring above 210°C. Upon heating, ammonium nitrate yields nitrous oxide (N20) gas and can be used as ail industrial source of that gas. Ammonium nitrate is soluble in H2O, slightly soluble in ethyl alcohol, moderately soluble in methyl alcohol, and soluble in acetic acid solutions containing NH3. 

Diphenyl tellurium hydroxybromide, (C6H5)2Te(OH)Br, may be obtained by treating the dibromide with water or the corresponding hydroxychloride with sodium or potassium bromide. It melts at 26-4° to 265° C., is moderately soluble in methyl alcohol but sparingly soluble in boiling water. Treatment with acetic acid yields the dibromide, and the mother-liquors from this give a substance which is probably the diacetate. The latter with 5 per cent, sodium hydroxide gives the oxide. 

Because of its insolubility in common aprotic solvents, iodosylbenzene is of limited use for uncatalyzed oxidations in such media. The o-tert-butylsulfonyl derivative 6 of iodosylbenzene, on the other hand, is moderately soluble (0.08 M) in chloroform and has been employed for uncatalyzed oxidations of sulfides and phosphines to sulfoxides and phosphine oxides (Scheme 3) [17]. 

Inhaled anesthetics that are relatively insoluble in blood (low blood gas partition coefficient) and brain are eliminated at faster rates than more soluble anesthetics. The washout of nitrous oxide, desflurane, and sevoflurane occurs at a rapid rate, which leads to a more rapid recovery from their anesthetic effects compared to halothane and isoflurane. Halothane is approximately twice as soluble in brain tissue and five times more soluble in blood than nitrous oxide and desflurane its elimination therefore takes place more slowly, and recovery from halothane anesthesia is predictably less rapid. The duration of exposure to the anesthetic can also have a marked effect on the time of recovery, especially in the case of more soluble anesthetics. Accumulation of anesthetics in tissues, including muscle, skin, and fat, increases with continuous inhalation (especially in obese patients), and blood tension may decline slowly during recovery as the anesthetic is gradually eliminated from these tissues. Thus, if exposure to the anesthetic is short, recovery may be rapid even with the more soluble agents. However, after prolonged anesthesia, recovery may be delayed even with anesthetics of moderate solubility such as isoflurane. 

The reaction of OH radical with DMDS is fast and OH is moderately soluble in water (Henry s law constant is 25 M atm-1 at 25 C. But again, it depends on the concentration levels of DMDS in clouds and rainwater. In addition, the low solubility of DMDS in water makes heterogeneous oxidation in water droplets unlikely. 

Methyldiiodoarsine [m.p. 30° b.p. 128° (16 mm.)] forms odorless yellow needles which melt to a red liquid and volatilize without decomposition at 200°. The compound is somewhat soluble in water and moderately soluble in alcohol, ether, and carbon disulfide the solubility is increased by the presence of hydrogen iodide. Hydrogen chloride or bromide converts the diiodoarsine into the corresponding chloro or bromo compound, while iodine oxidizes the compound to methylarsenic oxide.8 When boiled with dry sodium carbonate in the presence of benzene, methyldiiodoarsine forms the corresponding oxide.5... 

All oxides (O2 ) and hydroxides (OH-) are insoluble except those of allkali metals and certain alkaline earth metals (Group DA Ca, Sr, Ba, Ra). Ca(OH)2 is moderately soluble. 

Lead nitrate is one of the most readily prepared salts of lead, since it is of moderate solubility and can be obtained in well-formed anhydrous crystals, Pb(NOs)2. In it lead appears in its usual state of oxidation, which corresponds to that of the oxide PbO indeed, the salt is actually prepared by treating this oxide (litharge) with nitric acid. 

Ferroverdin can be crystallized following chromatography on alumina. C3oH2o08N2Fe-H20. No decomp. <300°. Moderately soluble in alcoholic solvents, sparingly soluble in ether and practically insoluble in water. Rf in n-butanol-pyridine-water 60 40 30, 0.91. Rt values known in three other solvents. Absorption peaks in the visible at approximately 4300 and 6750 A with amM = 8.2 and 8.8, respectively. Iron is diamagnetic (36) and resistant to EDTA, dipyridyl, ortho-phenanthroline and l-nitroso-2-napthol-3,6-disulfonic acid. The color is discharged with Na2S204 and other reductants but is unaffected by various oxidative treatments. 

The hydrous oxide is soluble in adds and to some extent in bases. On boiling [Fe(H20)6]3+ with Ba(OH)2, crystalline Ba3[Fe(OH)6]2 can be obtained and moderate concentrations of [Fe(OH)6]3" can be maintained in strong base solution. 

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