Potassium chlorate, solubility

Quantitatively, sulfur in a free or combined state is generally determined by oxidizing it to a soluble sulfate, by fusion with an alkaH carbonate if necessary, and precipitating it as insoluble barium sulfate. Oxidation can be effected with such agents as concentrated or fuming nitric acid, bromine, sodium peroxide, potassium nitrate, or potassium chlorate. Free sulfur is normally determined by solution in carbon disulfide, the latter being distilled from the extract. This method is not useful if the sample contains polymeric sulfur. 

Manufacture. Most chlorate is manufactured by the electrolysis of sodium chloride solution in electrochemical cells without diaphragms. Potassium chloride can be electroly2ed for the direct production of potassium chlorate (35,36), but because sodium chlorate is so much more soluble (see Fig. 2), the production of the sodium salt is generally preferred. Potassium chlorate may be obtained from the sodium chlorate by a metathesis reaction with potassium chloride (37). 

Potassium chlorate is less satisfactory because of its lower solubility. 

Exhaustive oxidation of sulphones to sulphate using a mixture of potassium chlorate, sodium peroxide and sugar in a bomb has also been recommended220. This procedure is known as the Parr method and produces a mixture of soluble alkali sulphates. 

Upon heating anthraquinone with fuming sulphuric acid at 160° for about 1 hour, the main product Is anthraquinone-p-sulphonic acid, which is isolated as the sparingly soluble sodium salt. The latter when heated imder pressure with sodium hydroxide solution and an oxidising agent (sodium or potassium chlorate) yields first the corresponding hydroxy compound further hydroxy-lation occurs in the a-position through oxidation by the chlorate and 1 2-di-hydroxyanthraquinone (alizarin) is formed. 

Tetraphosphorus trisulfide (P4S3) which is also called phosphorus sesquisulfide, can be obtained by heating a stoichiometric mixture of phosphorus and sulfur at 180 °C in an inert atmosphere. The compound (m.p. 174 °C) is soluble in toluene, carbon disulfide, and benzene, and it is used with potassium chlorate, sulfur, and lead dioxide in matches. 

Potassium chlorate may be prepared by mixing concentrated solutions of sodium chlorate and potassium chloride. Potassium chlorate crystallizes when the solubility product [K+] [ClOs j is exceeded. 

Fusion of polonium dioxide with a potassium chlorate/hydroxide mixture gives a bluish solid (colorless when hot) which is more soluble in water than the corresponding polonite (Po032 ) this presumably contains some potassium polonate. The trioxide may possibly be formed by strongly heating polonium dioxide and chromium trioxide in air (12). 

The presence of a certain excess of base prevents the conversion of the hypochlorite into chlorate and chloride, whereas it is rapidly effected when the acid is in excess. It is therefore necessary to add the acid to the alkaline substance in quantity insufficient for saturation, and constantly to agitate the bottle immersed in cold water and not to reverse the operation by gradually saturating the acid with the base. By taking these precautions, cone. soln. of hypochlorous acid and potash may be used without precipitating potassium chlorate, notwithstanding the sparing solubility of this salt. This proves that u any chlorate is formed, the quantity is very small. 

The rapidity with which sulphuric acid decomposes potassium chlorate is well known. If small quantities of the salt are treated with the acid, with the precaution of fusing the salt in the retort and, when cold, pouring sulphuric acid on the mass, the violence of tho reaction is rednced, and, at a convenient temp., a gas is disengaged which can be collected over mercury, and which is designated deutoxide of chlorine. The residue in the retort contains potassium sulphate, and sparingly soluble unknown salt of a new acid (perchloric acid). 

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 of potassium chlorate in water has been determined by G. J. Mulder, J. L. Gay Lussac, C. A. Gerardin, L. TschugaefE and W. Chlopin, and B. Pawlewsky.19 The latter found (a) the percentage amount of potassium chlorate in the sat. soln. and (b) the amount of the salt dissolved by 100 parts of water ... 

The solubility of potassium chlorate is depressed by the addition of other potassium salts, or by the addition of other chlorates F. Winteler, and T. Schlosing have measured the solubility of potassium chlorate in potassium chloride soln. and of sodium chlorate in soln. of sodium chloride. In accord with the general rule, the solubility is diminished by the addition of a salt with a common ion. S. Arrhenius measured the solubility of potassium chlorate in aq. soln. of potassium nitrate and C. Blarez in aq. soln. of potassium bromide, chloride, iodide, nitrate, sulphate, oxalate, and hydroxide H. T. Calvert, and J. N. Bronsted in an aq. soln. of the last-named compound. H. T. Calvert also measured the solubility of potassium... 

Lithium chlorate is very soluble in alcohol the chlorates of the other alkalies having a low solubility in this menstruum. Potassium chlorate is precipitated from its aq. soln. by the addition of alcohol or acetone. The solubility of potassium chlorate 20 in absolute alcohol, acetone, ether, and chloroform is virtually nil, and in aq. alcohol or acetone, at a constant temp., the solubility increases as the proportion. of water increases. For example, at 30° the number of grams of potassium chlorate which are dissolved in 100 grms. (a) of soln., (h) of water when the solvent contains p per cent, of alcohol ... 

A. Wachter and G. C. Wittstein have shown that the solubility of sodium chlorate is also much smaller in alcohol than in water. 100 grms. of alcohol dissolve one gram of sodium chlorate at 25°, and 2-5 grms. at the b.p. 100 grms. of a 77 per cent. soln. of alcohol at 16°, dissolve 2"94 grms. of sodium chlorate. Similarly aq. acetone, at 30°, dissolves the following amounts of potassium chlorate ... 

Chlorate. Potassium chlorate, [CAS 3811-04-9], chlorate of potash, KCIO, white solid, soluble, mp about 350°C, powerful oxidizing agent, and consequently a fire hazard with dry organic materials, such as clothes, and with sulfur upon heating oxygen is liberated and the residue is potassium chloride formed by electrolysis of potassium chloride solution under proper conditions, Used (l)m matches, (2) in pyrotechnics, (3) as disinfectant, (4) as a source of oxygen upon heating, (Hazardous Use of potassium perchlorate is recommended instead )... 

Perchlorate. Potassium perchlorate. [CAS 7778-74-7]. KCKU. white solid, very slightly soluble, mp 610°C, but above 400VC decomposes with evolution of oxygen gas and formation of potassium chloride residue formed (1) by electrolysis of potassium chlorate under proper conditions. (2) by heating potassium chlorate at 48(UC and then fractional crystallization. Used (1) as a convenient and safe (preferred to use of potassium chlorate) method of preparing oxygen by heating, (2) 111 the determination of potassium in soluble salt solution. 

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