|a ductile malleable silvery-white element of the platinum metal group occurring principally in nickel-bearing ores: used as a hydrogenation catalyst and, alloyed with gold, in jewellery. Symbol: Pd; atomic no: 46; atomic wt: 106.42; valency: 2, 3, or 4; relative density: 1202; melting pt: 1555°C; boiling pt: 2964°C|
|[C19: named after the asteroid |
|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|
|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
palladium pal·la·di·um (pə-lā'dē-əm)
A soft ductile metallic element occurring naturally with platinum, especially in gold, nickel, and copper ores, and used as a catalyst in hydrogenation. Atomic number 46; atomic weight 106.4; melting point 1,555°C; boiling point 2,963°C; specific gravity 12.02 (20°C); valence 2, 3, 4.
|palladium (pə-lā'dē-əm) Pronunciation Key
A malleable, ductile, grayish-white metallic element that occurs naturally with platinum. It is used as a catalyst in hydrogenation and in alloys for making electrical contacts and jewelry. Atomic number 46; atomic weight 106.4; melting point 1,552°C; boiling point 3,140°C; specific gravity 12.02 (20°C); valence 2, 3, 4. See Periodic Table.