Page:Proceedings of the Royal Society of London Vol 1.djvu/92

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and found it to contain common muriate of potash 84, hyperoxy- genized muriate 16. But by the proportions established above, 16 byperoxygenized muriate contain 6 of oxygen, and this, with the acid contained in the whole 100 of entire salt, gives the proportions,

Oxygen . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Muriatic acid . . . . . . . . . . . . . . . . . . . . . . . . 84 100

These proportions differ a little from those obtained by Mr. Ber- thollet and by Mr. Cruikshank; the former mentions 11 per cent. of oxygen, the. latter 43. But Mr. Berthollet, in all probability, used an acid which already contained a little simple muriatic acid, or else he did not expel all the oxygen from his oxygenized mi'r‘riatic acid by the light of the sun. And Mr. Cruikshank having made use of hyperoxygenized muriate of potashi‘and muriatic acid1 to obtain that which he examined, the result was a mixture of oxygenized and hyperoxygenized muriatic acid gases.

Having stated the proportions of the acids, the author passes on to the examination of the salts. Oxygenized muriates are decom- posed at the very moment of their formation, and are resolved into common muriates and hyperoxygenized muriates. To prove this, Mr. Chenevix asserts that he always obtained the same proportion of muriate of silver, by pouring some nitrate of that metal into the re- cent liquor of the entire salt, as into some that he had evaporated. But he concludes that the acid does really come into contact with the alkali, and unite with it, in the state of oxygenized muriatic acid, because ammonia is decomposed by a current of that acid; and am- monia (as is afterwards proved) is not decomposed either by common or by hyperoxygcnized muriatic acid. From this experiment he con- cludes also, that hyperoxygenized muriatic acid has a much greater affinity than oxygenized muriatic acid to the salifiable bases.

Mr. Chenevix then passes to the examination of the hyperoxyge< nized muriates. These are all formed by the resolution of the ele- ments of oxygenized muriates into common muriates and hyperoxy- genized muriates. They have properties that characterize them fully. The acid is expelled by all acids, except the benzoic, acetic, acetous, boracic, prussic, and carbonic ; and the order of affinity of the salifiable alkaline and earthy bases is potash, soda, barytes, strontia, lime, am- monia, magnesia, alumina, and silica.

The first species is, therefore, hyperoxygenized muriate of potash, which the author thinks can exist in two states. It was from this salt chiefly that he attempted to disengage the acid. If sulphuric acid be poured upon it, a crackling noise is heard, and an orange-coloured liquor, with greenish yellow fumes, is disengaged; but the acid can- not thus be obtained pure, as the heat necessary to bring it over is sufficient to decompose it. In attempting to distil this mixture a violent explosion ensued as soon as heat was applied. As a caution to those who would repeat the experiment, Mr. Chenevix describes an accident which happened to Dr. Vandier, by which that gentle-