Chemistry
Unlike other groups, the members of this family do not show patterns in its electron configuration, as two lighter members of the group are exceptions from the Aufbau principle:
| Z | Element | Numerical Bohr model |
|---|---|---|
| 24 | chromium | 2, 8, 13, 1 |
| 42 | molybdenum | 2, 8, 18, 13, 1 |
| 74 | tungsten | 2, 8, 18, 32, 12, 2 |
| 106 | seaborgium | 2, 8, 18, 32, 32, 12, 2 |
Most of the chemistry has been observed only for the first three members of the group, the chemistry of seaborgium is not very established and therefore the rest of the section deals only with its upper neighbors in the periodic table. The elements in the group, like those of groups 7—11, have high melting points, and form volatile compounds in higher oxidation states. All the elements of the group are relatively nonreactive metals with a high melting points (1907 °C, 2477 °C, 3422 °C); that of tungsten is the highest of all metals. The metals form compounds in different oxidation states: chromium forms compounds in all states from −2 to +6: disodium pentacarbonylchromate, disodium decacarbonyldichromate, bis(benzene)chromium, tripotassium pentanitrocyanochromate, chromium(II) chloride, chromium(III) oxide, chromium(IV) chloride, potassium tetraperoxochromate(V), and chromium(VI) dichloride dioxide; the same is also true for molybdenum and tungsten, but the stability of the +6 state grows down the group. Depending on oxidation states, the compounds are basic, amphoteric, or acidic; the acidity grows with the oxidation state of the metal.
Read more about this topic: Group 6 Element
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