Chromium group
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Position in the periodic table
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| group | 6th |
| period | |
| 4th |
24 Cr |
| 5 |
42 Mon |
| 6th |
74 W |
| 7th |
106 Sg |
The 6th group of the periodic table contains the elements chromium , molybdenum , tungsten and the element 106 seaborgium , which was first produced in 1974 . The group is also called the chromium group after the first member .
All metals from the group have similar chemical properties (in the form of oxidation states +2, +3 and +6). Molybdenum and tungsten are more similar to one another than chromium, with the most stable oxidation state at +3 , with an almost identical atomic radius with the most stable oxidation state +6. As high-melting and high-boiling elements, all members are important alloy components. Tungsten is the metal with the highest melting point and the second highest boiling point.
| Surname | chrome | molybdenum | tungsten | Seaborgium |
|---|---|---|---|---|
| Melting point | 2130 K (1857 ° C) | 2896 K (2623 ° C) | 3695 K (3422 ° C) | ? |
| boiling point | 2945 K (2672 ° C) | 4912 K (4639 ° C) | 5828 K (5555 ° C) | ? |
| density | 7.14 g cm −3 | 10.28 g cm −3 | 19.25 g cm −3 | ? |
| Appearance | silvery metallic | silver-white to steel-gray metallic |
shiny white metallic |
? |
| Atomic radius | 140 pm | 145 pm | 146 pm | ? |
- The metals
Chromium Crystals, 99.999% +
crystalline molybdenum, 99.99%
vapor-deposited tungsten crystals, 99.98%
Individual evidence
- ^ Wissenschaft-Online-Lexika: Entry on chromium group in the Lexikon der Physik , accessed on February 21, 2009.
- ↑ Web elements (chrome)
- ↑ Web elements (molybdenum)
- ↑ Web elements (tungsten)