m]
| a silver-white metallic element, used as an alloy with iron in making hard, high-speed cutting tools. Symbol: Mo; atomic weight: 95.94; atomic number: 42; specific gravity: 10.2. |

mo·lyb·de·num (mə-lĭb'də-nəm) n. Symbol Mo A hard, silvery-white metallic element used to toughen alloy steels and soften tungsten alloy. An essential trace element in plant nutrition, it is used in fertilizers, dyes, enamels, and reagents. Atomic number 42; atomic weight 95.94; melting point 2,617°C; boiling point 4,612°C; specific gravity 10.22 (at 20°C); valence 2, 3, 4, 5, 6. See Table at element. [New Latin, from earlier molybdena, lead ore, from Latin molybdaena, galena, from Greek molubdaina, from molubdos, lead.] |
molybdenum mo·lyb·de·num (mə-lĭb'də-nəm)
n.
Symbol Mo
A hard metallic element that is an essential trace element in plant and animal nutrition. Atomic number 42; atomic weight 95.94; melting point 2,623°C; boiling point 4,639°C; specific gravity 10.22 (at 20°C); valence 2, 3, 4, 5, 6.
| molybdenum (mə-lĭb'də-nəm) Pronunciation Key
Symbol Mo A hard, silvery-white metallic element that resists corrosion and retains its strength at high temperatures. It is used to harden and toughen steel and to make high-temperature wiring. Molybdenum is an essential trace element in plant metabolism. Atomic number 42; atomic weight 95.94; melting point 2,617°C; boiling point 4,612°C; specific gravity 10.22 (at 20°C); valence 2, 3, 4, 5, 6. See Periodic Table. |