Vanadium group

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    Vanadium    Group ►
group 5
period
4th 23
V
5 41
Nb
6th 73
days
7th 105
Db

The 5th group of the periodic table contains the elements vanadium , niobium , tantalum and the element 105 dubnium , which was first produced in 1967 . The group is also known as the vanadium group after the first member .

All metals from the group have similar chemical properties (in the form of oxidation states +5 and +3). Niobium and tantalum often occur together in nature due to the atomic and ionic radii being almost identical due to the lanthanide contraction . The oxides of vanadium, niobium and tantalum were previously referred to as acid earths or earth acids because of their acidic character.

Properties of the vanadium group metals
Surname Vanadium niobium Tantalum Dubnium
Melting point 2183 K (1910 ° C) 2750 K (2477 ° C) 3290 K (3017 ° C) ?
boiling point 3680 K (3407 ° C) 5017 K (4744 ° C) 5731 K (5458 ° C) ?
density 6.11 g cm −3 8.57 g cm −3 16.65 g cm −3 ?
Appearance steel gray metallic,
shimmering bluish
gray metallic gray metallic ?
Atomic radius 135 pm 145 pm 145 pm ?

Individual evidence

  1. ^ Wissenschaft-Online-Lexika: Entry on vanadium group in the Lexikon der Physik , accessed on February 21, 2009
  2. ^ Mineralienatlas.de Niobium. Retrieved September 14, 2010.
  3. Web elements (vanadium)
  4. Web elements (niobium)
  5. Web elements (tantalum)