Sulphurated Potash

Triturate the sulphurated potash in a porcelain mortar, and gradually add the lard, rubbing them together until the ointment is perfectly smooth and free from grittiness. This ointment, when used, should be recently prepared. 

Sulphurated potash (Liver of Sulphur) consists of a mixture of potassium polysulphides, thiosulphate and other salts. It is standardised on its total sulphur content determined by the alkaline bromine oxidation method given above under Sulphur. 

If only the monocarboxybc acid is required, the ester after hydrolysis with potash may be strongly acidified with sulphuric acid and the mixture heated under reflux the mineral acid promotes decarboxylation at a temperature just above 100°. The net result is the replacement of the halogen atom of the alkyl halide by —CH COOH thus in the above example ... 

World Survey of Potash Resources, 2nd ed.. The British Sulphur Corp. Ltd., London, 1966. 

A s/cr.s possess a fruity smell and usually distil without decomposition. Boil with refltiK for 5 minutes on the water-btith a few c.c. of the licpiid with 3 to 4 volumes of a ten pei cent, solution of ctLListic potash in methyl alcohol and pour into water. Notice if the liquid dissolves and has lost the odour of the ester. An ester will be completely hydrolysed, and if the alcohol is soluble in water a clear solution will be obtained. If the alcohol is vol.atile and the solution neiitialised w ith sulphuric acid. and evaporated on the water-bath, the alkali salt of the organic acid mixed with pottissium sulphate will be left and the acid may be investigated as desciibed under 1. If it is required to. ascertain the nature of the alcohol in the ester, hydrolysis must fig effected with a strong aqueous solution of caustic potash... 

The identification of camphene is best carried out by its conversion into isobomeol under the influence of acetic acid in the presence of sulphuric acid. In order to effect this conversion, 100 grams of the fraction containing the terpene in substantial quantity are mixed with 250 grains of glacial acetic acid and 10 grams of 50 per cent, sulphuric acid. Tne mixture is heated for two to three hours on a water-bath to a temperature of 50° to 60°. At first the liquid separates into two layers, bat soon becomes homogeneous and takes on a pale red colour. Excess of water is added, and the oil which is precipitated, and which contains the isobomeol in the form of its acetate, is well washed with water repeatedly. It is then saponified by heating with alcoholic potash solution on a water-bath. The liquid is then evaporated and extracted with water, and the residue recrystallised from petroleum ether. 

Oil saponified by solution of potash in unpurified methylated spirit. Excess of alkali neutialised by hydrochloric acid, and the acids liberated, previous to distillation by sulphuric acid 47 28... 

A blank experiment, employing for distillation the residue resulting from the evaporation of 25 c.c. of the alcoholic potash used in 5, previously neutralised by means of sulphuric acid. 

A reaction between sodium from the glass and atmospheric water and carbon dioxide can lead to the formation of sodium carbonate, which crystallizes in fine needles. A potash glass forms potassium carbonate, which is too deliquescent to crystallize out. A lead glass can react with hydrogen sulphide, and to a smaller extent with carbon dioxide, sulphur dioxide, and acid vapoiurs. 

One of the most important and versatile building blocks for the construction of biomolecules is hydrogen cyanide HCN (also known as pmssic acid), which was prepared for the first time by the German-Swedish apothecary Carl-Wilhelm Scheele (1742-1786) in Koping in Sweden. He heated blood with potash and charcoal and obtained what he called Blutlauge , which he distilled with sulphuric acid (Bauer, 1980 Encycl. Am., 1975). 

The simplest way of considering those bodies is, to conceive the supersalts to be compounded of two atoms of acid with one of the base, and the subsalts of two atoms of base with one of acid. Thus supersulphate of potash is composed of one atom of potash united to two of sulphuric acid, or by weight of 33 parts of base and 54 of acid. ... 

H. Erdmann s apparatus for preparing hydrogen chloride in a Kipp s apparatus is illustrated in Fig. 9. The middle bulb of the Kipp s apparatus contains pumice stone the upper and lower bulbs contain hydrochloric acid the upper end of Kipp s apparatus is closed by a rubber stopper fitted with a bulb containing potash lye. The separating funnel contains cone, sulphuric acid, and it leads to the inner bulb via a trap A containing sufficient mercury to cover the opening of the down-tube from the separatory funnel. Otherwise the diagram explains itself. A wash-bottle can be fitted to the exit tube B in the ordinary way. 

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