Solubility sodium-potassium example

Potassium borohydride is similar in properties and reactions to sodium borohydride, and can similarly be used as a reducing agent for removing aldehydes, ketones and organic peroxides. It is non-hygroscopic and can be used in water, ethanol, methanol or water-alcohol mixtures, provided some alkali is added to minimise decomposition, but it is somewhat less soluble than sodium borohydride in most solvents. For example, the solubility of potassium borohydride in water at 25° is 19g per lOOmL of water (as compared to sodium borohydride, 55g). 

G. S. Serullas treated potassium chlorate with an excess of hydrofluosilicic acid the clear liquid was decanted from the sparingly soluble potassium fluosilicate, the soln. evaporated below 30°, and filtered through glass powder J. J. Berzelius evaporated the acid liquid mixed with finely divided silica below 30° in air, or over cone, sulphuric acid and potassium hydroxide in vacuo. The excess of hydrofluoric acid was volatilized as silicon fluoride, and the clear liquid was then filtered from the excess of silica. R. Bottger treated sodium chlorate with oxalic acid whereby sparingly soluble sodium oxalate was formed J. L. Wheeler, and T. B. Munroe treated sodium chlorate with hydrofluosilicic acid and M. Brandau treated potassium chlorate with aluminium sulphate and sulphuric acid and precipitated the alum so formed with alcohol. Chloric acid is formed in many reactions with hypochlorous and chlorous acid for example, it is formed when an aq. soln. of chlorine or hypochlorous or chlorous acid decomposes in light. It is also formed when an aq. soln. of chlorine dioxide stands in darkness or in light. A mixture of alkali chlorate and chlorite is formed when an aq. soln. of an alkali hydroxide is treated with chlorine dioxide. 

The solubility diagrams of several species are shown in Fig. 2, and these illustrate the importance of solubility behavior in the selection of the mode of crystallization. For example, consider the differences between potassium nitrate and sodium chloride The solubility of potassium nitrate is strongly influenced by the system temperature, whereas the opposite is true for sodium chloride. As a consequence, (1) a high yield of potassium nitrate crystals can be obtained by cooling a saturated feed solution,... 

Deliquescence is a property of substances very soluble in water. When such substances, potassium carbonate or calcium chloride for example, are exposed to the air, the water vapor forms with the substance a small quantity of a saturated solution. This saturated solution has a lower vapor pressure than that of the atmosphere, that is, the water is held by the substance, it does not tend to escape, hence more water vapor is added from the air, and finally the substance is entirely dissolved in this condensed vapor. Common salt or sodium chloride often appears to deliquesce, but the deliquescence is due to the very soluble magnesium and calcium chlorides which are usually mixed with commercial sodium chloride. Sodium nitrate is very soluble in water at the ordinary temperature, but potassium nitrate is only slightly soluble. Hence potassium nitrate, and not sodium nitrate, is used in the manufacture of gunpowder. 

Among all chromium compounds only the hexavalent salts are a prime health hazard. Cr + is more readily taken up by cells, than any other valence state of the metal. Occupational exposure to these compounds can produce skin ulceration, dermatitis, perforation of the nasal septa, and kidney damage. It can induce hypersensitivity reactions of the skin and renal tubular necrosis. Examples of hexavalent salts are the chromates and dichromates of sodium, potassium, and other metals. The water-soluble hexavalent chromium salts are absorbed into the bloodstream through inhalation. Many chromium(VI) compounds are carcinogenic, causing lung cancers in animals and humans. The carcinogenicity may be attributed to intracellular conversion of Cr + to Cr +,... 

The commonest strong bases are the water-soluble hydroxides of sodium, potassium, calcium, barium and lithium. These are all ionic solids. Since they are strong bases they are completely ionized in water. For example, NaOH(s) breaks up completely in water producing Na" (aq) and OH (aq) ... 

The latter equation shows that the nitrate concentration in equilibrium with atmospheric nitrogen is proportionate with the value of redox potential and at Eh < 0.71 should not exceed 1 mmole-l" (62 mg-1 )- Salts of nitrate display high solubility (sodium saltpetre NaNOj - 876 g kg k potassium salpetre KNO - 316 g-kg S nitroammit (NH) NOj - 1,880 g-kg" nitrobarite Ba(NOj)2 - 90.5 g-kg Setc.). The nitrate practically does not take part in complexation and is not adsorbed, and that is why it is removed from water with difficulty. Natural accumulation of sodium salts (saltpetres) are extremely rare and found in conditions of arid climate. An example is sodium saltpetre (NaNO ) on the coast of Chile. 

In the second example, a dyestuff manufacturer presented a question in which a salt presumed to be the sodium salt of trisulfonic acid is less soluble than the potassium or mixed sodium-potassium salt. The questioner used potassium carbonate to dissolve the sodium salt and produce a higher concentration solution. The questioner believed that the chromaphore was the sulfonate anion, and not the salt, and asked whether the eight possible salts... 

Nearly all compounds containing the nitrate, sodium, potassium, and ammonium ions are soluble in water. Most salts containing the chloride and sulfate ions are soluble in water, with specific exceptions (see Table 7.1). Most compounds containing the hydroxide, sulfide, carbonate, and phosphate ions are not soluble in water (unless the compound also contains Na, K, or NH4 ). For example, suppose we combine barium chloride and sulfuric acid solutions ... 

Highly soluble salts (for example sodium fluoride, potassium chloride, potassium citrate) are preferably not prepared in a capsule at all, since rapid dissolution can result in a high local concentration that may be harmful to the mucosa of the gastro-intestinal tract. An enteric coating on capsules and tablets can protect the gastric mucosa from irritating active substances. But the preparation of an oral solution of the active substance may be a better alternative. 

Only 11 elements can be considered major components of seasalt the cations sodium, potassium, magnesium, calcium and strontium, and the anions chloride, sulphate, bromide, hydrogen carbonate (carbonate), borate (borid acid) and fluoride. These major dissolved constituents (concentrations > 1 mg/kg in ocean waters) make up > 99 % of the soluble ionic species of seawater. The elemental ratios are relatively constant throughout the world ocean, and their concentrations change due to the addition or substruction of water only (concept of conservatism ). Therefore, it is possible to characterize the composition by determining only one constituent that is easy to measure and is conservative in its behaviour. An example is chlorinity (Cl, as defined in Section 11.2.4). 

In general, random SBR with a low amount of block styrene and low amounts of 1,2-butadiene enchainment (<20%) can be prepared in the presence of small amounts of added potassium or sodium metal alkoxides. " For example, at 50 °C in the presence of as little as 0.067 equivalents of potassium t-butoxide in cyclohexane, the amormt of bound styrene was relatively independent of conversion, in contrast to the heterogeneity observed in the absence of randomizer, that is, tapered block copolymer formation. " The polybutadiene microstmcrnre obtained tmder these conditions corresponds to about 15% 1,2-microstmctrue. Using 0.2 equivalents of hydrocarbon-soluble sodium 2,3-dimethyl-2-pentoxide, the monomer reactivity ratios for alkyllithium-initiated SBR were fotmd to be of re = 1.1 and rs = 0.1. The resulting copolymer had only 5% block styrene and 18% 1,2-vinyl microstmctrue. It was found that there is a very narrow compositional window ([RONa]/[RLi]) at... 

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