Solubility in strong acid

It is soluble in strong acids (20-36% HCI or ION H2SO4) and is rapidly saponified upon standing. 

The fact that the equilibrium constant is huge implies that Zn(OH)2 is extremely soluble in strong acid. 

Poly(benzimidazole)s possess excellent thermal stability, flame resistance, and outstanding chemical resistance. The solubility of hexafluoroisopropyli-dene-unit-containing poly(benzimidazole)s is remarkably improved.24 They are readily soluble in strong acids such as formic acid, concentrated sulfuric acid, and methanesulfonic acid and in aprotic polar solvents such as DMAc and NMP. The polymer from tetramine (23) is soluble even in m-cresol and pyridine. 

The aromatic poly(benzothiazole) from 15 and 29 is almost amorphous and easily soluble in strong acids such as concentrated sulfuric acid and methane-sulfonic acid.26 It also dissolves in organic solvents such as HMPA and o-chlorophenol. The increased solubility and amorphous nature of this polymer is also ascribed to reduced intermolecular forces and to looser packing owing to the presence of highly distorted diphenylhexafluoroisopropylidene units in the polymer backbone. 

As diazonium tetrafluoroborates are more soluble in strongly acidic media, the precipitation of the diazonium tetrafluoroborate from an auxiliary diazonium salt and alkaline tetrafluoroborate is preferred when the diazonium tetrafluoroborate is thought to be too soluble an increase of the ionic strength tends to decrease its solubility.3-129 However, some alkaline chloride can co-precipitate with the diazonium tetrafluoroborate. Consequently, the diazonium tetrafluoroborate yields can be a little optimistic and some chlorinated aromatics can be produced together with fluorinated aromatics during the dediazoniation step.3,171 To prevent such contamination, the diazonium tetrafluoroborate is washed with the minimum amount of chilled water, then with another polar solvent, such as an alcohol, and finally with a water-insoluble solvent, such as diethyl ether. When their decomposition points are not too low, diazonium tetrafluoroborates can also be purified by rccrystallization (in water or acetic acid) or by dissolution in acetone then salting out with diethyl ether.3... 

Resistance to acids/bases soluble in strong acids insoluble... 

Calcium Oxalate. CaCtOj, white precipitate, insoluble in weak acids, but soluble in strong acids, formed by reaction of soluble calcium salt solution and ammonium oxalate solution. Solubility at I8°C 0.0056 g anhydrous salt per liter of saturated solution. 

The product is in the form of colorless crystals which are somewhat water repellent. It is insoluble in alkali but is saponified upon standing in alkaline suspension (3% ammonia). It is soluble in strong acids (20-36% HCI or 10 N H2S04) and is rapidly saponified upon standing. 

If you recall from Chapter 14, the term amphoteric refers to a substance that can act as either an acid or a base. Many metal oxides and hydroxides that are fairly insoluble in water are quite soluble in strongly acidic and basic solutions. These materials can dissolve in both acids and bases because they are amphoteric—that is, they are capable of acting like acids or bases. One example is zinc hydroxide, Zn(OH)2. Zinc hydroxide is quite insoluble in water (Ksp = 3 X 10 17). However, if placed in a strong acid, the hydroxide ion reacts with the hydrogen ion in the acid in the following way ... 

This solution is prepared by mixing SO g. of concentrated hydrochloric acid and 400 ml. of water. The aldehyde has appreciable solubility in strongly acidic solutions. 

Sodium Aluminosilicate occurs as a fine, white, amorphous powder, or as beads. It is a series of hydrated sodium aluminum silicates having Na20 Al203 Si02 molar ratios of approximately 1 1 13, respectively. It is insoluble in water and in alcohol and other organic solvents, but at 80° to 100°, it is partially soluble in strong acids and solutions of alkali hydroxides. 

The precipitate is almost insoluble in water (0-053 g -1, Ks = 2-25 x 10 8) potassium is precipitated quantitatively if a small excess of the reagent is applied (01-0-2 per cent). The precipitate is soluble in strong acids and alkalis, and also in acetone. Rubidium, caesium, thallium(I), and ammonium ions interfere. 

Black crystalline CuO is obtained by pyrolysis of the nitrate or other oxo salts above 800°C it decomposes to Cu20. The hydroxide is obtained as a blue bulky precipitate on addition of alkali hydroxide to cupric solutions warming an aqueous slurry dehydrates this to the oxide. The hydroxide is readily soluble in strong acids and also in concentrated alkali hydroxides, to give deep blue anions, for example, [Cu(OH)4]2" and [Cu(OH)6]4". In aqueous ammonia deep blue ammine complexes are formed, as described later. 

The c/s-[aquabis(ethylenediamine)hydroxochromium(III)] dithionate salt is stable for years. It is insoluble in water but very soluble in strong acid and strong base, giving the corresponding m-diaqua and m-dihydroxo species. The crude product is used in the preparation of m-[diaquabis(ethylenediamine)chromium-(III)] bromide (Sec. G) and of di-/a-hydroxobis[bis(ethylenediamine)chromium-(III)] dithionate (Sec. J). 

The untreated polymers are Insoluble in most conventional organic solvents and are only soluble in strong acids such as concentrated sulphuric, dichloroacetic and trifluoroacetic acids. 

Sucralfate, Sucralfate. 3.4.5.6-tctra-(polyhydn>xyalu-minum)-cr-i>-glucupyranusyl sulfate-2.3.4.5-tctra-(polyhj-druxyuluminum)-j D-fructofuranoside sulfate (Carafatc). is the aluminum hydroxide complex of the octasulfate ester ot sucrose. It is practically insoluble in water and soluble in strong acids and bases, it has a pK value between 0.43 anJ 1.19. 

It is sometimes asserted that carbonates are soluble in strong acids because a gas is formed that escapes (CO2). Suppose that CO2 were extremely soluble in water (as, for example, ammonia is) and therefore it did not leave the site of the reaction, but that otherwise, its chemistry was unchanged. Would calcium carbonate be soluble in strong acids Explain. 

Properties Yellow crystals. D 6.123, mp 844C. Soluble in strong acids and alkalies insoluble in water. 

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