Search the Dictionary

Occlusion of gases (Chem. & Physics), the phenomenon of absorbing gases, as exhibited by platinum, palladium, iron, or charcoal; thus, palladium absorbs, or occludes, nearly a thousand times its own volume of hydrogen, and in this case a chemical compound seems to be formed.

A rare metallic element of the platinum group, found native as an alloy in platinum ore, and in iridosmine. It is a hard, infusible, bluish or grayish white metal, and the heaviest substance known. Its tetroxide is used in histological experiments to stain tissues. Symbol Os. Atomic weight 191.1. Specific gravity 22.47…

A rare metallic element of the light platinum group, found native, and also alloyed with platinum and gold. It is a silver-white metal resembling platinum, and like it permanent and untarnished in the air, but is more easily fusible. It is unique in its power of occluding hydrogen, which it does to the extent of nearly…

al set of teeth which fits to the mouth, and holds the teeth in place. It may be of gold, platinum, silver, rubber, celluloid, etc.

Platinum. Platina mohr, platinum black. -- Platina yellow, a pigment prepared from platinum.

Of, pertaining to, or containing, platinum; -- used specifically to designate those compounds in which the element has a higher valence, as contrasted with the platinous compounds; as, platinic chloride (PtCl4).

Yielding platinum; as, platiniferous sand.

A natural alloy of platinum and iridium occurring in grayish metallic rounded or cubical grains with platinum.

To cover or combine with platinum.

A double chloride of platinum and some other metal or radical; a salt of platinochloric acid.

A double cyanide of platinum and some other metal or radical; a salt of platinocyanic acid.

Resembling platinum.

A permanent photographic picture or print in platinum black.

Of, pertaining to, or containing, platinum; -- used specifically to designate those compounds in which the element has a lower valence, as contrasted with the platinic compounds; as, platinous chloride (PtCl2).

A rare element of the light platinum group. It is found in platinum ores, and obtained free as a white inert metal which it is very difficult to fuse. Symbol Rh. Atomic weight 104.1. Specific gravity 12.

A rare element of the light platinum group, found associated with platinum ores, and isolated as a hard, brittle steel-gray metal which is very infusible. Symbol Ru. Atomic weight 103.5. Specific gravity 12.26. See Platinum metals, under Platinum.

An arsenide of platinum occuring in grains and minute isometric crystals of tin-white color. It is found near Sudbury, Ontario Canada, and is the only known compound of platinum occuring in nature.

West Indies. -- Horse sponge, a coarse commercial sponge, especially Spongia equina. -- Platinum sponge. (Chem.) See under Platinum. -- Pyrotechnical sponge, a substance made of mushrooms or fungi, which are boiled in water, dried, and beaten, then put in a strong lye prepared with saltpeter, and again dried in an o…

ing fluids, like a sponge. Spongy lead (Chem.), sponge lead. See under Sponge. -- Spongy platinum. See under Platinum.

by the application of heat. Paquelin's thermocautery, thermocautery by means of a hollow platinum point, which is kept constantly hot by the passage through it of benzine vapor.