History
The discovery of all elements in the group led to controversies. The verification of those discoveries was difficult due to similarity of vanadium and group 6 element chromium, the chemical similarity of niobium and tantalum and the complicated setup which was necessary to produce a few atoms of dubnium.
Read more about this topic: Group 5 Element
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—Henry David Thoreau (1817–1862)
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—Anton Pavlovich Chekhov (1860–1904)
“Perhaps universal history is the history of the diverse intonation of some metaphors.”
—Jorge Luis Borges (1899–1986)