Answer | Crossword Clue |
---|---|
praseodymium | rare-earth, metallic, trivalent element, named from its green salts. Symbol: Pr; at. wt.: 140.91; at. no.: 59; sp. gr.: 6.77 at 20┬░C |
gallium | rare, steel-gray, trivalent metallic element used in high-temperature thermometers because of its high boiling point (1983┬░C) and low melting point (30┬░C). Symbol: Ga; at. wt.: 69.72; at. no.: 31; sp. gr.: 5.91 at 20┬░C |