R 265 at 15° C., possessing a somewhat sweet taste; below o° C. it solidifies to a white crystalline mass, which melts at 17° C. When heated alone it partially volatilizes, but the greater part decomposes; under a pressure of 12 mm.
The oxychloride, bromides, and other compounds were subsequently discovered; here we need only notice Moissan's preparation of the trifluoride and Thorpe's discovery of the pentafluoride, a compound of especial note, for it volatilizes unchanged, giving a vapour of normal density and so demonstrating the stability of a pentavalent phosphorus compound (the pentachloride and pentabromide dissociate into a molecule of the halogen element and phosphorus trichoride).
This artifice is specially valuable when the substance decomposes or volatilizes in a warm current of carbon dioxide.
It forms a white silky mass which volatilizes at about 400° C. It deliquesces in moist air, and is decomposed violently by water.
In the oxyhydrogen flame silver boils, forming a blue vapour, while platinum volatilizes slowly, and osmium, though infusible, very readily.
It crystallizes in white plates, which melt at 45° C. and boil at 302° C. It is almost insoluble in water, but readily volatilizes in steam.
Neville determined it to be 1061 7° C.; Daniel Berthelot gives 1064° C., while Jaquerod and Perrot give 1066.1-1067.4° C. At still higher temperatures it volatilizes, forming a reddish vapour.
It has also been shown that gold volatilizes when a gold-amalgam is distilled.
(a) Hofmann's is the best if the substance volatilizes at below 310°, and does not react on mercury; otherwise (b) Demuth and Meyer's, Eykman's, Schall's, or other methods may be used.
The barium salt is extracted by water and boiled with nitric acid, when the osmium volatilizes in the form of its tetroxide.
The salt volatilizes (mostly in the form of a mixed vapour of the two components, which reunite on cooling), and condenses in the dome in the form of a characteristically fibrous and tough crust.
It readily volatilizes, and if moisture be rigorously excluded, it does not dissociate, but in the presence of mere traces of water it dissociates into ammonia and hydrochloric acid (H.
The salt crystallizes in cubes of specific gravity 1.995; it melts at about 800° and volatilizes at a bright red heat.
It volatilizes slowly at ordinary temperatures, but rapidly on heating.
The residue is then heated in a current of superheated steam, in which the boric acid volatilizes and distils over.
It crystallizes in colourless cubes and volatilizes when heated very strongly.
The tetrachloride, WC1 41 is obtained by partial reduction of the higher chlorides with hydrogen; a mixture of the pentaand hexa-chloride is distilled in a stream of hydrogen or carbon dioxide, and the pentachloride which volatilizes returned to the flask several times.
The dioxybromide forms light red crystals or a yellow powder; it volatilizes at a red heat, and is not acted upon by water.
Silver melts at about rooo C.; recent determinations give 960.7° (Heycock and Neville) and 962° (Becquerel); at higher temperatures it volatilizes with the formation of a pale blue vapour (Stas).
It crystallizes in needles or prisms and volatilizes when heated, giving a pale yellow vapour.