Page:Proceedings of the Royal Society of London Vol 2.djvu/52

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and oxygen, he now gives the name of oxyiodine; and to its compounds with water, oxyiodic acid. To this same compound M. Gay-Lussac has given the name of iodic acid, and for the salts he uses the generic term iodates; but to this the author objects, that hydriodic and chloriodic acids may each be as well entitled to the appellation of iodic acids as a generic name, and that the termination in at places those bodies, which he calls oxyiodes, in the common class of neutral salts, from which they differ in many respects; while the term oxyiodes expresses more definitely the nature of a combination, which has the closest analogy with the bodies termed hyperoxymuriates.

On the Action of Acids on the Salts usually called Hyperoxymuriates, and on the Gases produced from them.By Sir Humphry Davy, LL.D. F.R.S.Read May 4, 1815.[Phil. Trans. 1815, p. 214.]

M. Gay-Lussac having obtained, by the action of sulphuric acid on hyperoxymuriate of barytes, a peculiar compound, to which he gave the name of chloric acid, the author was induced to examine the action of this and other acids on the hyperoxymuriate of potash, and after various attempts, found the following process with sulphuric acid to be the best. A small quantity, not exceeding fifty or sixty grains, of the hyperoxymuriate are to be mixed with a small quantity of the acid in its concentrated state, and to be rubbed together by means of a spatula of platina till incorporated into a solid mass of a bright orange colour. This mass having been introduced into a small retort, is to be then warmed by immersion in water gradually heated, but kept below the boiling point. As the heat rises, an elastic fluid is emitted of a bright yellowish green colour. This gas may be received over mercury, on which it has no action; but it is rapidly absorbed by water. Its smell is aromatic, without any smell of chlorine. It destroys vegetable blues, without previously reddening them. By a temperature of 212° it explodes with more violence than euchlorine, expanding more, and producing more light. After the explosion the volume is found increased in the proportion of 2 to 3; two parts of the product being oxygen, and the remainder chlorine.

Phosphorus introduced into this gas occasions an explosion, and burns in the liberated gases with its usual brilliancy; but other combustible bodies have no action on the gas.

Water saturated with the gas is of a deep yellow colour; it does not taste sour, but astringent and corrosive, leaving a lasting and disagreeable impression on the tongue.

It appears to the author not impossible, that the gas to which he formerly gave the name of euchlorine, may be a mixture of the new gas with chlorine; and indeed the action of water upon euchlorine favours this idea, since it acquires the same colour from it, and leaves a residuum of chlorine; but, on the contrary, the circumstance that Dutch foil has no action upon euchlorine, seems to show that it contains no free chlorine merely intermixed, but that the whole is chemically combined.