A rare element of the chromium group, occurring in nature in the minerals molybdenite and wulfenite, and when reduced obtained as a hard, silver-white, difficulty fusible metal. Symbol Mo. Atomic weight 95.9.
- 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.