XII. On fluoride of silver. —Part II

Abstract

On account of the prospect of being able to isolate fluorine by means of the action of chlorine, bromine, or iodine on argentic fluoride, I have in this investigation very fully examined the behaviour of those substances with that compound. Behaviour with Chlorine (continued). —To ascertain more completely the nature of the compound formed by fluoride of silver with chlorine and platinum at a red heat, I passed a very slow current of pure chlorine over 24.62 grains of argentic fluoride in a platinum boat within a 20-inch platinum tube during nine hours at a very low red heat. A very minute amount of a vapour which corroded glass was continually evolved ; and traces of a sublimate occurred, consisting chiefly of argentic chloride. On heating the boat and tube to redness after the experiment, a boiling sound was heard, a little fume and much chlorine escaped, and a loss of weight of 11.70 grains took place. On weighing the cooled apparatus a gain of 6.49 grains upon the original weight still remained, theory requiring 6.88 grains if the whole of the fluoride took up its equivalent of chlorine with­ out any fluorine being expelled. The thick platinum boat was powerfully corroded, and immoveably fixed to the tube, even at a red heat. The residuary salt was easily fusible, tasteless, of a dark red colour, and contained much combined platinum ; 3.38 grains of it fused with alkaline carbonates yielded 2.56 grains of metal (theory requiring 2.51 grains), of which by analysis 1.82 grain was found to be silver, and .74 grain was platinum: .63 grain of chlorine was also found in it, showing that the chlorine in it was chemically equivalent in amount to the silver. The deficiency of .19 grain required to make up the quantity taken I have set down as fluorine. The red salt corroded glass in the presence of damp air, and contained only a few very minute particles of platinum.